Initial project commit

2020-07-18 21:44:27 -04:00
parent 8a1141b373
commit fea891a268
127 changed files with 20838 additions and 0 deletions
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/AuthChallengeRxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/AuthChallengeRxMessage.java
@@ -0,0 +1,25 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import com.eveningoutpost.dexdrip.Models.JoH;
+
+import java.nio.ByteOrder;
+import java.util.Arrays;
+
+/**
+ * Created by joeginley on 3/16/16.
+ */
+public class AuthChallengeRxMessage extends BaseMessage {
+    public static final int opcode = 0x03;
+    public byte[] tokenHash;
+    public byte[] challenge;
+    private final static String TAG = G5CollectionService.TAG; // meh
+    public AuthChallengeRxMessage(byte[] data) {
+        UserError.Log.d(TAG,"AuthChallengeRX: "+ JoH.bytesToHex(data));
+        if (data.length >= 17) {
+            if (data[0] == opcode) {
+                tokenHash = Arrays.copyOfRange(data, 1, 9);
+                challenge = Arrays.copyOfRange(data, 9, 17);
+            }
+        }
+    }
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/AuthChallengeTxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/AuthChallengeTxMessage.java
@@ -0,0 +1,25 @@
+package com.eveningoutpost.dexdrip.G5Model;
+import com.eveningoutpost.dexdrip.G5Model.TransmitterMessage;
+import com.eveningoutpost.dexdrip.Models.JoH;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+
+/**
+ * Created by joeginley on 3/16/16.
+ */
+public class AuthChallengeTxMessage extends TransmitterMessage {
+    byte opcode = 0x04;
+    byte[] challengeHash;
+
+    public AuthChallengeTxMessage(byte[] challenge) {
+        challengeHash = challenge;
+
+        data = ByteBuffer.allocate(9);
+        data.put(opcode);
+        data.put(challengeHash);
+
+        byteSequence = data.array();
+        UserError.Log.d(TAG,"AuthChallengeTX: "+ JoH.bytesToHex(byteSequence));
+    }
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/AuthRequestTxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/AuthRequestTxMessage.java
@@ -0,0 +1,50 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import com.eveningoutpost.dexdrip.Models.JoH;
+import com.eveningoutpost.dexdrip.Models.UserError;
+
+import java.io.UnsupportedEncodingException;
+import java.nio.ByteBuffer;
+import java.util.UUID;
+
+import static com.eveningoutpost.dexdrip.utils.CipherUtils.getRandomKey;
+
+/**
+ * Created by joeginley on 3/16/16.
+ */
+@SuppressWarnings("FieldCanBeLocal")
+public class AuthRequestTxMessage extends BaseMessage {
+    public final byte opcode = 0x01;
+    public byte[] singleUseToken;
+    private final byte endByteStd = 0x2;
+    private final byte endByteAlt = 0x1;
+
+
+    public AuthRequestTxMessage(int token_size) {
+        this(token_size, false);
+    }
+
+    public AuthRequestTxMessage(int token_size, boolean alt) {
+        byte[] uuidBytes = getRandomKey();
+        final UUID uuid = UUID.nameUUIDFromBytes(uuidBytes);
+
+        try {
+            uuidBytes = uuid.toString().getBytes("UTF-8");
+        } catch (UnsupportedEncodingException e) {
+            e.printStackTrace();
+        }
+
+        final ByteBuffer bb = ByteBuffer.allocate(token_size);
+        bb.put(uuidBytes, 0, token_size);
+        singleUseToken = bb.array();
+
+        data = ByteBuffer.allocate(token_size + 2);
+        data.put(opcode);
+        data.put(singleUseToken);
+        data.put(alt ? endByteAlt : endByteStd);
+
+        byteSequence = data.array();
+        UserError.Log.d(TAG, "New AuthRequestTxMessage: " + JoH.bytesToHex(byteSequence));
+    }
+}
+
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/AuthStatusRxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/AuthStatusRxMessage.java
@@ -0,0 +1,35 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+
+import com.eveningoutpost.dexdrip.Models.UserError;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+
+/**
+ * Created by joeginley on 3/16/16.
+ */
+public class AuthStatusRxMessage extends BaseMessage {
+    public static final int opcode = 0x5;
+    public int authenticated;
+    public int bonded;
+
+    public AuthStatusRxMessage(byte[] packet) {
+        if (packet.length >= 3) {
+            if (packet[0] == opcode) {
+                data = ByteBuffer.wrap(packet).order(ByteOrder.LITTLE_ENDIAN);
+
+                authenticated = data.get(1);
+                bonded = data.get(2);
+                UserError.Log.d(TAG,"AuthRequestRxMessage:  authenticated:"+authenticated+"  bonded:"+bonded);
+            }
+        }
+    }
+
+    public boolean isAuthenticated() {
+        return authenticated == 1;
+    }
+    public boolean isBonded() {
+        return bonded == 1;
+    }
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/BackFillRxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/BackFillRxMessage.java
@@ -0,0 +1,30 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+
+// created by jamorham
+
+public class BackFillRxMessage extends BaseMessage {
+
+    public static final int opcode = 0x51;
+    private static final int length = 20;
+
+    private boolean valid = false;
+
+    BackFillRxMessage(byte[] packet) {
+
+        if (packet.length == length) {
+            data = ByteBuffer.wrap(packet).order(ByteOrder.LITTLE_ENDIAN);
+            if ((data.get() == opcode) && checkCRC(packet)) {
+                valid = true;
+                // meh
+                // 51 00 01 01 A1A00200 DDAF0200 82000000 2361 1625
+            }
+        }
+    }
+
+    public boolean valid() {
+        return valid;
+    }
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/BackFillStream.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/BackFillStream.java
@@ -0,0 +1,131 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+// created by jamorham
+
+import com.eveningoutpost.dexdrip.Models.JoH;
+import com.eveningoutpost.dexdrip.Models.UserError;
+import com.eveningoutpost.dexdrip.UtilityModels.Pref;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+import java.util.LinkedList;
+import java.util.List;
+
+import lombok.AllArgsConstructor;
+import lombok.Data;
+
+import static com.eveningoutpost.dexdrip.G5Model.DexTimeKeeper.fromDexTimeCached;
+
+public class BackFillStream extends BaseMessage {
+
+    private int last_sequence = 0;
+
+    BackFillStream() {
+        data = ByteBuffer.allocate(1000);
+        data.order(ByteOrder.LITTLE_ENDIAN);
+    }
+
+    public synchronized void push(byte[] packet) {
+
+        if (packet == null) return;
+        final int this_sequence = (int) packet[0];
+        if (this_sequence == last_sequence + 1) {
+            last_sequence++;
+
+            for (int i = 2; i < packet.length; i++) {
+                if (data.position() < data.limit()) {
+                    data.put(packet[i]);
+                } else {
+                    UserError.Log.wtf(TAG, "Reached limit for backfill stream size");
+                }
+            }
+        } else {
+            UserError.Log.wtf(TAG, "Received backfill packet out of sequence: " + this_sequence + " vs " + (last_sequence + 1));
+        }
+    }
+
+    public List<Backsie> decode() {
+        final List<Backsie> backsies = new LinkedList<>();
+
+        int extent = data.position();
+        data.rewind();
+        final int length = data.getInt();
+        // TODO check length
+        while (data.position() < extent) {
+            final int dexTime = data.getInt();
+            final int glucose = data.getShort();
+            final byte type = data.get();
+            final byte trend = data.get();
+
+            final CalibrationState state = CalibrationState.parse(type);
+
+            switch (state) {
+                case Ok:
+                case NeedsCalibration:
+                    insertBackfillItem(backsies, dexTime, glucose, trend);
+                    break;
+
+                case WarmingUp:
+                    break;
+
+                case Errors:
+                    /* This preference option has never been available outside of unit testing
+                       and can now be removed.
+                    if (Pref.getBooleanDefaultFalse("ob1_g5_use_errored_data")) {
+                        insertBackfillItem(backsies, dexTime, glucose, trend);
+                    }
+                    */
+                    break;
+
+                case InsufficientCalibration:
+                    if (Pref.getBoolean("ob1_g5_use_insufficiently_calibrated", true)) {
+                        insertBackfillItem(backsies, dexTime, glucose, trend);
+                    }
+                    break;
+
+                case NeedsFirstCalibration:
+                case NeedsSecondCalibration:
+                case Unknown:
+                    break;
+
+                default:
+                    UserError.Log.wtf(TAG, "Encountered backfill data we don't recognise: " + type + " " + glucose + " " + trend + " " + " " + JoH.dateTimeText(fromDexTimeCached(dexTime)));
+                    break;
+
+            }
+        }
+        return backsies;
+
+
+    }
+
+    private void insertBackfillItem(List<Backsie> backsies, int dexTime, int glucose, byte trend) {
+        if (dexTime != 0) {
+            backsies.add(new Backsie(glucose, trend, dexTime));
+        }
+    }
+
+    public void enumerate(int size) {
+
+        System.out.println("Size:" + size);
+        byte[] output = data.array();
+        int i = 4;
+        while (i < data.position()) {
+            if ((i - 4) % size == 0) {
+                System.out.println("");
+            }
+            System.out.print(JoH.bytesToHex(new byte[]{output[i]}));
+            i++;
+        }
+        System.out.println("\n");
+    }
+
+    @Data
+    @AllArgsConstructor()
+    public class Backsie {
+        private final int glucose;
+        private final int trend;
+        private final int dextime;
+    }
+
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/BackFillTxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/BackFillTxMessage.java
@@ -0,0 +1,38 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import com.eveningoutpost.dexdrip.Models.JoH;
+import com.eveningoutpost.dexdrip.Models.UserError;
+
+import static com.eveningoutpost.dexdrip.G5Model.DexTimeKeeper.getDexTime;
+
+// created by jamorham
+
+public class BackFillTxMessage extends BaseMessage {
+
+    final byte opcode = 0x50;
+    final int length = 20;
+
+    public BackFillTxMessage(int startDexTime, int endDexTime) {
+        init(opcode, length);
+        data.put((byte) 0x5);
+        data.put((byte) 0x2);
+        data.put((byte) 0x0);
+        data.putInt(startDexTime);
+        data.putInt(endDexTime);
+        data.put(new byte[6]);
+        appendCRC();
+        UserError.Log.d(TAG, "BackfillTxMessage dbg: " + JoH.bytesToHex(byteSequence));
+    }
+
+    public static BackFillTxMessage get(String id, long startTime, long endTime) {
+
+        final int dexStart = getDexTime(id, startTime);
+        final int dexEnd = getDexTime(id, endTime);
+        if (dexStart < 1 || dexEnd < 1) {
+            UserError.Log.e(TAG, "Unable to calculate start or end time for BackFillTxMessage");
+            return null;
+        }
+        return new BackFillTxMessage(dexStart, dexEnd);
+    }
+
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/BaseAuthChallengeTxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/BaseAuthChallengeTxMessage.java
@@ -0,0 +1,18 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import com.eveningoutpost.dexdrip.Models.JoH;
+import com.eveningoutpost.dexdrip.Models.UserError;
+
+// jamorham
+
+public class BaseAuthChallengeTxMessage extends BaseMessage {
+    static final byte opcode = 0x04;
+
+    public BaseAuthChallengeTxMessage(final byte[] challenge) {
+
+        init(opcode, 9);
+        data.put(challenge);
+        byteSequence = data.array();
+        UserError.Log.d(TAG, "BaseAuthChallengeTX: " + JoH.bytesToHex(byteSequence));
+    }
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/BaseGlucoseRxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/BaseGlucoseRxMessage.java
@@ -0,0 +1,52 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+
+import lombok.NoArgsConstructor;
+
+/**
+ * Created by jamorham on 02/07/2018.
+ *
+ */
+
+@NoArgsConstructor
+public abstract class BaseGlucoseRxMessage extends BaseMessage {
+
+    private final static String TAG = G5CollectionService.TAG; // meh
+
+    public TransmitterStatus status;
+    public int status_raw;
+    public int timestamp;
+    public int unfiltered;
+    public int filtered;
+    public int sequence; // : UInt32
+    public boolean glucoseIsDisplayOnly; // : Bool
+    public int glucose; // : UInt16
+    public int state; //: UInt8
+    public int trend; // : Int8 127 = invalid
+
+
+    CalibrationState calibrationState() {
+        return CalibrationState.parse(state);
+    }
+
+    boolean usable() {
+        return calibrationState().usableGlucose();
+    }
+
+    boolean insufficient() {
+        return calibrationState().insufficientCalibration();
+    }
+
+    boolean OkToCalibrate() {
+        return calibrationState().readyForCalibration();
+    }
+
+    public Double getTrend() {
+        return trend != 127 ? ((double) trend) / 10d : Double.NaN;
+    }
+
+    public Integer getPredictedGlucose() {
+        return null; // stub
+    }
+
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/BaseMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/BaseMessage.java
@@ -0,0 +1,174 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import com.chrispr.bluetooth.BluetoothScanner;
+import com.eveningoutpost.dexdrip.Models.JoH;
+import com.eveningoutpost.dexdrip.Models.UserError;
+
+import com.google.gson.annotations.Expose;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.slf4j.Marker;
+import org.slf4j.MarkerFactory;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+import java.util.Locale;
+
+// jamorham
+
+public class BaseMessage {
+    protected static final String TAG = G5CollectionService.TAG; // meh
+    static final int INVALID_TIME = 0xFFFFFFFF;
+    @Expose
+    long postExecuteGuardTime = 50;
+    @Expose
+    public volatile byte[] byteSequence;
+    public ByteBuffer data;
+
+
+    void init(final byte opcode, final int length) {
+        data = ByteBuffer.allocate(length).order(ByteOrder.LITTLE_ENDIAN);
+        data.put(opcode);
+        if (length == 1) {
+            getByteSequence();
+        } else if (length == 3) {
+            appendCRC();
+        }
+    }
+
+    byte[] appendCRC() {
+        data.put(FastCRC16.calculate(getByteSequence(), byteSequence.length - 2));
+        return getByteSequence();
+    }
+
+    boolean checkCRC(byte[] data) {
+        if ((data == null) || (data.length < 3)) return false;
+        final byte[] crc = FastCRC16.calculate(data, data.length - 2);
+        return crc[0] == data[data.length - 2] && crc[1] == data[data.length - 1];
+    }
+
+    byte[] getByteSequence() {
+        return byteSequence = data.array();
+    }
+
+    long guardTime() {
+        return postExecuteGuardTime;
+    }
+
+    static long getUnsignedInt(ByteBuffer data) {
+        return ((data.get() & 0xff) + ((data.get() & 0xff) << 8) + ((data.get() & 0xff) << 16) + ((data.get() & 0xff) << 24));
+    }
+
+    static int getUnsignedShort(ByteBuffer data) {
+        return ((data.get() & 0xff) + ((data.get() & 0xff) << 8));
+    }
+
+    static int getUnsignedByte(ByteBuffer data) {
+        return ((data.get() & 0xff));
+    }
+
+    static String dottedStringFromData(ByteBuffer data, int length) {
+
+        final byte[] bytes = new byte[length];
+        data.get(bytes);
+        final StringBuilder sb = new StringBuilder(100);
+        for (byte x : bytes) {
+            if (sb.length() > 0) sb.append(".");
+            sb.append(String.format(Locale.US, "%d", (x & 0xff)));
+        }
+        return sb.toString();
+    }
+
+    static int getUnixTime() {
+        return (int) (JoH.tsl() / 1000);
+    }
+
+    public static class G5CollectionService {
+        public static String TAG = "Message";
+    }
+
+    public static class UserError {
+        public static class Log {
+            protected static final Logger logger = LoggerFactory.getLogger("Message");
+            public static Marker getMarker(String markerName) {
+                Marker m = MarkerFactory.getMarker(markerName);
+                return m;
+            }
+            public static void e(String a, String b){
+                //android.util.Log.e(a, b);
+                logger.error(getMarker(a), b);
+
+                //new com.eveningoutpost.dexdrip.Models.UserError(a, b);
+            }
+
+            public static void e(String tag, String b, Exception e){
+                //android.util.Log.e(tag, b, e);
+                logger.error(getMarker(tag), b, e);
+
+                //new com.eveningoutpost.dexdrip.Models.UserError(tag, b + "\n" + e.toString());
+            }
+
+            public static void w(String tag, String b){
+                //android.util.Log.w(tag, b);
+                logger.warn(getMarker(tag), b);
+                //com.eveningoutpost.dexdrip.Models.UserError.UserErrorLow(tag, b);
+            }
+            public static void w(String tag, String b, Exception e){
+                //android.util.Log.w(tag, b, e);
+                logger.warn(getMarker(tag), b, e);
+                //com.eveningoutpost.dexdrip.Models.UserError.UserErrorLow(tag, b + "\n" + e.toString());
+            }
+            public static void wtf(String tag, String b){
+                //android.util.Log.wtf(tag, b);
+                logger.error(getMarker(tag), b);
+                //com.eveningoutpost.dexdrip.Models.UserError.UserErrorHigh(tag, b);
+            }
+            public static void wtf(String tag, String b, Exception e){
+                //android.util.Log.wtf(tag, b, e);
+                logger.error(getMarker(tag), b, e);
+                //com.eveningoutpost.dexdrip.Models.UserError.UserErrorHigh(tag, b + "\n" + e.toString());
+            }
+            public static void wtf(String tag, Exception e){
+                //android.util.Log.wtf(tag, e);
+                logger.error(getMarker(tag), "Error", e);
+                //com.eveningoutpost.dexdrip.Models.UserError.UserErrorHigh(tag, e.toString());
+            }
+
+            public static void uel(String tag, String b) {
+                //android.util.Log.i(tag, b);
+                logger.info(getMarker(tag), b);
+                //com.eveningoutpost.dexdrip.Models.UserError.UserEventLow(tag, b);
+            }
+
+            public static void ueh(String tag, String b) {
+                //android.util.Log.i(tag, b);
+                logger.info(getMarker(tag), b);
+                //com.eveningoutpost.dexdrip.Models.UserError.UserEventHigh(tag, b);
+            }
+
+            public static void d(String tag, String b){
+                //android.util.Log.d(tag, b);
+                logger.debug(getMarker(tag), b);
+                //if(com.eveningoutpost.dexdrip.Models.UserError.ExtraLogTags.shouldLogTag(tag, android.util.Log.DEBUG)) {
+                //    UserErrorLow(tag, b);
+                //}
+            }
+
+            public static void v(String tag, String b){
+                //android.util.Log.v(tag, b);
+                logger.debug(getMarker(tag), b);
+                //if(com.eveningoutpost.dexdrip.Models.UserError.ExtraLogTags.shouldLogTag(tag, android.util.Log.VERBOSE)) {
+                //    UserErrorLow(tag, b);
+                //}
+            }
+
+            public static void i(String tag, String b){
+                //android.util.Log.i(tag, b);
+                logger.info(getMarker(tag), b);
+                //if(com.eveningoutpost.dexdrip.Models.UserError.ExtraLogTags.shouldLogTag(tag, android.util.Log.INFO)) {
+                //    UserErrorLow(tag, b);
+                //}
+            }
+        }
+    }
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/BatteryInfoRxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/BatteryInfoRxMessage.java
@@ -0,0 +1,53 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import com.eveningoutpost.dexdrip.Models.UserError;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+import java.util.Locale;
+
+/**
+ * Created by jamorham on 25/11/2016.
+ */
+
+
+public class BatteryInfoRxMessage extends BaseMessage {
+
+    private final static String TAG = G5CollectionService.TAG; // meh
+
+    public static final byte opcode = 0x23;
+
+    public int status;
+    public int voltagea;
+    public int voltageb;
+    public int resist;
+    public int runtime;
+    public int temperature;
+
+    public BatteryInfoRxMessage(byte[] packet) {
+        if (packet.length >= 10) {
+            data = ByteBuffer.wrap(packet).order(ByteOrder.LITTLE_ENDIAN);
+            if (data.get() == opcode) {
+                status = data.get();
+                voltagea = getUnsignedShort(data);
+                voltageb = getUnsignedShort(data);
+                resist = getUnsignedShort(data);
+                runtime = getUnsignedByte(data);
+                if (packet.length == 10) {
+                    runtime = -1; // this byte isn't runtime on rev2
+                }
+                temperature = data.get(); // not sure if signed or not, but <0c or >127C seems unlikely!
+            } else {
+                UserError.Log.wtf(TAG, "Invalid opcode for BatteryInfoRxMessage");
+            }
+        } else {
+            UserError.Log.wtf(TAG, "Invalid length for BatteryInfoMessage: " + packet.length);
+        }
+    }
+
+    public String toString() {
+        return String.format(Locale.US, "Status: %s / VoltageA: %d / VoltageB: %d / Resistance: %d / Run Time: %d / Temperature: %d",
+                TransmitterStatus.getBatteryLevel(status).toString(), voltagea, voltageb, resist, runtime, temperature);
+    }
+
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/BatteryInfoTxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/BatteryInfoTxMessage.java
@@ -0,0 +1,20 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import com.eveningoutpost.dexdrip.Models.JoH;
+import com.eveningoutpost.dexdrip.Models.UserError;
+
+/**
+ * Created by jamorham on 25/11/2016.
+ */
+
+public class BatteryInfoTxMessage extends BaseMessage {
+
+    private final static String TAG = G5CollectionService.TAG; // meh
+    static final byte opcode = 0x22;
+
+    public BatteryInfoTxMessage() {
+        init(opcode, 3);
+        UserError.Log.e(TAG, "BatteryInfoTx dbg: " + JoH.bytesToHex(byteSequence));
+    }
+}
+
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/BluetoothServices.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/BluetoothServices.java
@@ -0,0 +1,63 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+
+import java.util.HashMap;
+import java.util.UUID;
+
+/**
+ * Created by joeginley on 3/16/16.
+ */
+public class BluetoothServices {
+
+    //Transmitter Service UUIDs
+    public static final UUID DeviceInfo = UUID.fromString("0000180A-0000-1000-8000-00805F9B34FB");
+    //iOS uses FEBC?
+    public static final UUID Advertisement = UUID.fromString("0000FEBC-0000-1000-8000-00805F9B34FB");
+    public static final UUID CGMService = UUID.fromString("F8083532-849E-531C-C594-30F1F86A4EA5");
+    public static final UUID ServiceB = UUID.fromString("F8084532-849E-531C-C594-30F1F86A4EA5");
+
+    //DeviceInfoCharacteristicUUID, Read, DexcomUN
+    public static final UUID ManufacturerNameString = UUID.fromString("00002A29-0000-1000-8000-00805F9B34FB");
+
+    //CGMServiceCharacteristicUUID
+    public static final UUID Communication = UUID.fromString("F8083533-849E-531C-C594-30F1F86A4EA5");
+    public static final UUID Control = UUID.fromString("F8083534-849E-531C-C594-30F1F86A4EA5");
+    public static final UUID Authentication = UUID.fromString("F8083535-849E-531C-C594-30F1F86A4EA5");
+    public static final UUID ProbablyBackfill = UUID.fromString("F8083536-849E-531C-C594-30F1F86A4EA5");
+
+    //ServiceBCharacteristicUUID
+    public static final UUID CharacteristicE = UUID.fromString("F8084533-849E-531C-C594-30F1F86A4EA5");
+    public static final UUID CharacteristicF = UUID.fromString("F8084534-849E-531C-C594-30F1F86A4EA5");
+
+    //CharacteristicDescriptorUUID
+    public static final UUID CharacteristicUpdateNotification = UUID.fromString("00002902-0000-1000-8000-00805F9B34FB");
+
+    private static final HashMap<UUID, String> mapToName = new HashMap<>();
+
+
+    static {
+        mapToName.put(DeviceInfo, "DeviceInfo");
+        mapToName.put(Advertisement, "Advertisement");
+        mapToName.put(CGMService, "CGMService");
+        mapToName.put(ServiceB, "ServiceB");
+        mapToName.put(ManufacturerNameString, "ManufacturerNameString");
+        mapToName.put(Communication, "Communication");
+        mapToName.put(Control, "Control");
+        mapToName.put(Authentication, "Authentication");
+        mapToName.put(ProbablyBackfill, "ProbablyBackfill");
+        mapToName.put(CharacteristicE, "CharacteristicE");
+        mapToName.put(CharacteristicF, "CharacteristicF");
+        mapToName.put(CharacteristicUpdateNotification, "CharacteristicUpdateNotification");
+    }
+
+
+    public static String getUUIDName(UUID uuid) {
+        if (uuid == null) return "null";
+        if (mapToName.containsKey(uuid)) {
+            return mapToName.get(uuid);
+        } else {
+            return "Unknown uuid: " + uuid.toString();
+        }
+    }
+
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/BondRequestTxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/BondRequestTxMessage.java
@@ -0,0 +1,12 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+// jamorham
+
+public class BondRequestTxMessage extends BaseMessage {
+    static final byte opcode = 0x07;
+
+    public BondRequestTxMessage() {
+        init(opcode, 1);
+    }
+}
+
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/CRC.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/CRC.java
@@ -0,0 +1,25 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import com.eveningoutpost.dexdrip.ImportedLibraries.dexcom.CRC16;
+
+/**
+ * Created by jcostik1 on 3/24/16.
+ */
+public class CRC {
+
+    public static byte[] calculate(byte b) {
+        int crcShort = 0;
+        crcShort = ((crcShort >>> 8) | (crcShort << 8)) & 0xffff;
+        crcShort ^= (b & 0xff);
+        crcShort ^= ((crcShort & 0xff) >> 4);
+        crcShort ^= (crcShort << 12) & 0xffff;
+        crcShort ^= ((crcShort & 0xFF) << 5) & 0xffff;
+        crcShort &= 0xffff;
+        return new byte[] {(byte) (crcShort & 0xff), (byte) ((crcShort >> 8) & 0xff)};
+    }
+
+    public static byte[] calculate(byte[] bytes, int start, int end) {
+        return CRC16.calculate(bytes, 0, end);
+    }
+
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/CalibrateRxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/CalibrateRxMessage.java
@@ -0,0 +1,59 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+
+// created by jamorham
+
+public class CalibrateRxMessage extends BaseMessage {
+
+    public static final int opcode = 0x35;
+    private static final int length = 5;
+
+    private byte info = (byte) 0xff;
+    private byte result = (byte) 0xff;
+
+    CalibrateRxMessage(byte[] packet) {
+
+        if (packet.length == length) {
+            data = ByteBuffer.wrap(packet).order(ByteOrder.LITTLE_ENDIAN);
+            if ((data.get() == opcode) && checkCRC(packet)) {
+                info = data.get();
+                result = data.get();
+            }
+        }
+    }
+
+    boolean accepted() {
+        return result == 0x00 || result == 0x06 || result == 0x0D;
+    }
+
+    boolean wantsCalibration() {
+        return result == 0x06;
+    }
+
+    String message() {
+        // TODO i18n
+        switch (result) {
+
+            case (byte) 0x00:
+                return "OK";
+            case (byte) 0x01:
+                return "Code 1";
+            case (byte) 0x06:
+                return "Second calibration needed";
+            case (byte) 0x08:
+                return "Rejected";
+            case (byte) 0x0B:
+                return "Sensor stopped";
+            case (byte) 0x0D:
+                return "Duplicate";
+            case (byte) 0x0E:
+                return "Not ready to calibrate";
+            case (byte) 0xFF:
+                return "Unable to decode";
+            default:
+                return "Unknown code:" + result;
+        }
+    }
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/CalibrateTxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/CalibrateTxMessage.java
@@ -0,0 +1,25 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+
+// created by jamorham
+
+import com.eveningoutpost.dexdrip.Models.JoH;
+import com.eveningoutpost.dexdrip.Models.UserError;
+
+public class CalibrateTxMessage extends BaseMessage {
+
+    final byte opcode = 0x34;
+    final int length = 9;
+
+    final int glucose;
+
+    public CalibrateTxMessage(int glucose, int dexTime) {
+        init(opcode, length);
+        this.glucose = glucose;
+        data.putShort((short) glucose);
+        data.putInt(dexTime);
+        appendCRC();
+        UserError.Log.d(TAG, "CalibrateGlucoseTxMessage dbg: " + JoH.bytesToHex(byteSequence));
+    }
+
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/CalibrationState.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/CalibrationState.java
@@ -0,0 +1,142 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+// created by jamorham
+
+import android.util.SparseArray;
+
+import com.eveningoutpost.dexdrip.Models.UserError;
+import com.google.common.collect.ImmutableSet;
+
+import lombok.Getter;
+
+import static com.eveningoutpost.dexdrip.Services.G5CollectionService.TAG;
+
+public enum CalibrationState {
+
+    // TODO i18n
+
+    Unknown(0x00, "Unknown"),
+    Stopped(0x01, "Stopped"),
+    WarmingUp(0x02, "Warming Up"),
+    ExcessNoise(0x03, "Excess Noise"),
+    NeedsFirstCalibration(0x04, "Needs Initial Calibration"),
+    NeedsSecondCalibration(0x05, "Needs Second Calibration"),
+    Ok(0x06, "OK"),
+    NeedsCalibration(0x07, "Needs Calibration"),
+    CalibrationConfused1(0x08, "Confused Calibration 1"),
+    CalibrationConfused2(0x09, "Confused Calibration 2"),
+    NeedsDifferentCalibration(0x0a, "Needs More Calibration"),
+    SensorFailed(0x0b, "Sensor Failed"),
+    SensorFailed2(0x0c, "Sensor Failed 2"),
+    UnusualCalibration(0x0d, "Unusual Calibration"),
+    InsufficientCalibration(0x0e, "Insufficient Calibration"),
+    Ended(0x0f, "Ended"),
+    SensorFailed3(0x10, "Sensor Failed 3"),
+    TransmitterProblem(0x11, "Transmitter Problem"),
+    Errors(0x12, "Sensor Errors"),
+    SensorFailed4(0x13, "Sensor Failed 4"),
+    SensorFailed5(0x14, "Sensor Failed 5"),
+    SensorFailed6(0x15, "Sensor Failed 6"),
+    SensorFailedStart(0x16, "Sensor Failed Start");
+
+    @Getter
+    byte value;
+    @Getter
+    String text;
+
+
+    private static final SparseArray<CalibrationState> lookup = new SparseArray<>();
+    private static final ImmutableSet<CalibrationState> failed = ImmutableSet.of(SensorFailed, SensorFailed2, SensorFailed3, SensorFailed4, SensorFailed5, SensorFailed6, SensorFailedStart);
+    private static final ImmutableSet<CalibrationState> stopped = ImmutableSet.of(Stopped, Ended, SensorFailed, SensorFailed2, SensorFailed3, SensorFailed4, SensorFailed5, SensorFailed6, SensorFailedStart);
+
+
+    CalibrationState(int value, String text) {
+        this.value = (byte) value;
+        this.text = text;
+    }
+
+    static {
+        for (CalibrationState state : values()) {
+            lookup.put(state.value, state);
+        }
+    }
+
+    public static CalibrationState parse(byte state) {
+        final CalibrationState result = lookup.get(state);
+        if (result == null) UserError.Log.e(TAG, "Unknown calibration state: " + state);
+        return result != null ? result : Unknown;
+    }
+
+    public static CalibrationState parse(int state) {
+        return parse((byte) state);
+    }
+
+    public boolean usableGlucose() {
+        return this == Ok
+                || this == NeedsCalibration;
+    }
+
+    public boolean insufficientCalibration() {
+        return this == InsufficientCalibration;
+    }
+
+    public boolean readyForCalibration() {
+        return this == Ok
+                || needsCalibration();
+    }
+
+    public boolean needsCalibration() {
+        return this == NeedsCalibration
+                || this == NeedsFirstCalibration
+                || this == NeedsSecondCalibration
+                || this == NeedsDifferentCalibration;
+    }
+
+    public boolean sensorStarted() {
+        return !stopped.contains(this);
+    }
+
+    public boolean sensorFailed() {
+        return failed.contains(this);
+    }
+
+    public boolean ended() {
+        return this == Ended;
+    }
+
+    public boolean warmingUp() {
+        return this == WarmingUp;
+    }
+
+    public boolean ok() {
+        return this == Ok;
+    }
+
+    public boolean readyForBackfill() {
+       return this != WarmingUp && this != Stopped && this != Unknown && this != NeedsFirstCalibration && this != NeedsSecondCalibration && this != Errors;
+    }
+
+    public String getExtendedText() {
+        switch (this) {
+            case Ok:
+                if (DexSessionKeeper.isStarted()) {
+                    return getText() + " " + DexSessionKeeper.prettyTime();
+                } else {
+                    return getText() + " time?";
+                }
+            case WarmingUp:
+                if (DexSessionKeeper.isStarted()) {
+                    if (DexSessionKeeper.warmUpTimeValid()) {
+                        return getText() + "\n" + DexSessionKeeper.prettyTime() + " left";
+                    } else {
+                        return getText();
+                    }
+                } else {
+                    return getText();
+                }
+
+            default:
+                return getText();
+        }
+    }
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/DexResetHelper.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/DexResetHelper.java
@@ -0,0 +1,40 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import com.eveningoutpost.dexdrip.Models.JoH;
+import com.eveningoutpost.dexdrip.Models.UserError;
+import com.eveningoutpost.dexdrip.UtilityModels.CompatibleApps;
+
+import static com.eveningoutpost.dexdrip.UtilityModels.CompatibleApps.createActionIntent;
+import static com.eveningoutpost.dexdrip.UtilityModels.CompatibleApps.createChoiceIntent;
+import static com.eveningoutpost.dexdrip.UtilityModels.CompatibleApps.showNotification;
+import static com.eveningoutpost.dexdrip.UtilityModels.Constants.DEX_BASE_ID;
+
+// jamorham
+
+public class DexResetHelper {
+
+    private static final String TAG = "DexResetHelper";
+
+    public static void offer(String reason) {
+
+        if (JoH.pratelimit("offer-hard-reset-dex", 1200)) {
+            int id = DEX_BASE_ID;
+
+            final String title = "Hard Reset Transmitter?";
+
+            // piggybacking on the existing choice dialog system for compatible apps
+            showNotification(title, reason,
+                    createActionIntent(id, id + 1, CompatibleApps.Feature.HARD_RESET_TRANSMITTER),
+                    createActionIntent(id, id + 2, CompatibleApps.Feature.CANCEL),
+                    createChoiceIntent(id, id + 3, CompatibleApps.Feature.HARD_RESET_TRANSMITTER, title, reason),
+                    id);
+        } else {
+            UserError.Log.d(TAG, "Not offering reset as within rate limit");
+        }
+    }
+
+    public static void cancel() {
+        JoH.cancelNotification(DEX_BASE_ID);
+    }
+
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/DexSessionKeeper.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/DexSessionKeeper.java
@@ -0,0 +1,52 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import com.eveningoutpost.dexdrip.Models.JoH;
+import com.eveningoutpost.dexdrip.UtilityModels.Constants;
+import com.eveningoutpost.dexdrip.UtilityModels.PersistentStore;
+
+// jamorham
+
+// track active session time
+
+public class DexSessionKeeper {
+
+    private static final String PREF_SESSION_START = "OB1-SESSION-START";
+    private static final long WARMUP_PERIOD = Constants.HOUR_IN_MS * 2;
+
+    public static void clearStart() {
+        PersistentStore.setLong(PREF_SESSION_START, 0);
+    }
+
+    public static void setStart(long when) {
+        // TODO sanity check
+        PersistentStore.setLong(PREF_SESSION_START, when);
+    }
+
+    public static long getStart() {
+        // value 0 == not started
+        return PersistentStore.getLong(PREF_SESSION_START);
+    }
+
+    public static boolean isStarted() {
+        return getStart() != 0;
+    }
+
+    public static String prettyTime() {
+        if (isStarted()) {
+            final long elapsed = JoH.msSince(getStart());
+            if (elapsed < WARMUP_PERIOD) {
+                return JoH.niceTimeScalar((double) WARMUP_PERIOD - elapsed, 1);
+            } else {
+                return JoH.niceTimeScalar((double) elapsed, 1);
+            }
+        } else {
+            return "";
+        }
+    }
+
+    // check for mismatch between sensor state currency and transmitter time
+    public static boolean warmUpTimeValid() {
+        return (isStarted() && (JoH.msSince(getStart()) <= WARMUP_PERIOD));
+    }
+
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/DexSyncKeeper.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/DexSyncKeeper.java
@@ -0,0 +1,84 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+// jamorham
+
+import com.eveningoutpost.dexdrip.Models.JoH;
+import com.eveningoutpost.dexdrip.Models.UserError;
+import com.eveningoutpost.dexdrip.UtilityModels.Constants;
+import com.eveningoutpost.dexdrip.UtilityModels.PersistentStore;
+
+import static com.eveningoutpost.dexdrip.UtilityModels.BgGraphBuilder.DEXCOM_PERIOD;
+
+public class DexSyncKeeper {
+
+    private static final String TAG = DexTimeKeeper.class.getSimpleName();
+    private static final String DEX_SYNC_STORE = "DEX_SYNC_STORE-";
+    private static final long OLDEST_POSSIBLE = 1533839836123L;
+    private static final long GRACE_TIME = 5000;
+    private static final long VALIDITY_PERIOD = Constants.DAY_IN_MS;
+
+
+    // store sync time as now
+    public static void store(final String transmitterId) {
+        store(transmitterId, JoH.tsl());
+    }
+
+    // store sync time
+    public static void store(final String transmitterId, final long when) {
+
+        if ((transmitterId == null) || (transmitterId.length() != 6)) {
+            UserError.Log.e(TAG, "Invalid dex transmitter in store: " + transmitterId);
+            return;
+        }
+
+        if (when < OLDEST_POSSIBLE) {
+            UserError.Log.wtf(TAG, "Invalid timestamp to store: " + JoH.dateTimeText(when));
+            return;
+        }
+
+        PersistentStore.setLong(DEX_SYNC_STORE + transmitterId, when);
+        UserError.Log.d(TAG, "Sync time updated to: " + JoH.dateTimeText(when));
+    }
+
+    // anticpiate next wake up from now
+    public static long anticipate(final String transmitterId) {
+        return anticipate(transmitterId, JoH.tsl());
+    }
+
+    // anticipate next wake up from time
+    // -1 means we don't know anything
+    static long anticipate(final String transmitterId, final long now) {
+        final long last = PersistentStore.getLong(DEX_SYNC_STORE + transmitterId);
+        if (last < OLDEST_POSSIBLE) {
+            return -1;
+        }
+        if (last > now) {
+            UserError.Log.e(TAG, "Anticipation time in the future! cannot use: " + JoH.dateTimeText(last));
+            return -1; // can't be in the future
+        }
+
+        if (now - last > VALIDITY_PERIOD) {
+            UserError.Log.e(TAG, "Anticipation time too old to use: " + JoH.dateTimeText(last));
+            return -1;
+        }
+
+        final long modulo = (now - last) % DEXCOM_PERIOD;
+        if ((modulo < GRACE_TIME) && ((now - last) > GRACE_TIME)) return now;
+        final long next = now + (DEXCOM_PERIOD - modulo);
+        return next;
+    }
+
+    public static boolean isReady(final String transmitterId) {
+        return anticipate(transmitterId, JoH.tsl()) != -1;
+    }
+
+    // are we outside connection window?
+    // TODO also handle waking up before window PRE_GRACE_TIME = 20seconds?
+    public static boolean outsideWindow(final String transmitterId) {
+        final long now = JoH.tsl();
+        final long next = anticipate(transmitterId, now);
+        return next != now;
+    }
+
+}
+
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/DexTimeKeeper.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/DexTimeKeeper.java
@@ -0,0 +1,140 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import com.eveningoutpost.dexdrip.Models.JoH;
+import com.eveningoutpost.dexdrip.Models.UserError;
+import com.eveningoutpost.dexdrip.UtilityModels.PersistentStore;
+
+/**
+ * Created by jamorham on 25/11/2016.
+ */
+
+public class DexTimeKeeper {
+    private static final String TAG = DexTimeKeeper.class.getSimpleName();
+
+    private static final String DEX_XMIT_START = "DEX_XMIT_START-";
+    private static final long OLDEST_ALLOWED = 1512245359123L;
+    private static final long DEX_TRANSMITTER_LIFE_SECONDS = 86400 * 120;
+
+    private static String lastTransmitterId = null;
+
+    // update the activation time stored for a transmitter
+    public static void updateAge(final String transmitterId, final int dexTimeStamp) {
+        updateAge(transmitterId, dexTimeStamp, false);
+    }
+
+    // update the activation time stored for a transmitter
+    public static void updateAge(final String transmitterId, final int dexTimeStamp, final boolean absolute) {
+
+        if ((transmitterId == null) || (transmitterId.length() != 6)) {
+            UserError.Log.e(TAG, "Invalid dex transmitter in updateAge: " + transmitterId);
+            return;
+        }
+        if (dexTimeStamp < 1) {
+            UserError.Log.e(TAG, "Invalid dex timestamp in updateAge: " + dexTimeStamp);
+            if (dexTimeStamp == 0 && absolute) {
+                DexResetHelper.offer("Your transmitter clock has stopped or never started. Do you want to hard reset it?");
+            }
+            return;
+        }
+        final long longDexTimeStamp = (long) dexTimeStamp;
+        final long activation_time = JoH.tsl() - (longDexTimeStamp * 1000L);
+
+        if (activation_time > JoH.tsl()) {
+            UserError.Log.wtf(TAG, "Transmitter activation time is in the future. Not possible to update: " + dexTimeStamp);
+            return;
+        }
+
+        UserError.Log.d(TAG, "Activation time updated to: " + JoH.dateTimeText(activation_time));
+        PersistentStore.setLong(DEX_XMIT_START + transmitterId, activation_time);
+
+    }
+
+    public static int getDexTime(String transmitterId, long timestamp) {
+
+        if ((transmitterId == null) || (transmitterId.length() != 6)) {
+            UserError.Log.e(TAG, "Invalid dex transmitter in getDexTime: " + transmitterId);
+            return -3;
+        }
+        if (timestamp < OLDEST_ALLOWED) {
+            UserError.Log.e(TAG, "Invalid timestamp in getDexTime: " + timestamp);
+            return -2;
+        }
+
+        final long transmitter_start_timestamp = PersistentStore.getLong(DEX_XMIT_START + transmitterId);
+
+        if (transmitter_start_timestamp < OLDEST_ALLOWED) {
+            if (JoH.ratelimit("no-valid-dex-timestamp-log", 60)) {
+                UserError.Log.e(TAG, "No valid timestamp stored for transmitter: " + transmitterId);
+            }
+            return -1;
+        }
+
+        final long ms_since = timestamp - transmitter_start_timestamp;
+        if (ms_since < 0) {
+            UserError.Log.e(TAG, "Invalid timestamp comparison for transmitter id: " + transmitterId + " since: " + ms_since + "  requested ts: " + JoH.dateTimeText(timestamp) + " with tx start: " + JoH.dateTimeText(transmitter_start_timestamp));
+            return -4;
+        }
+        lastTransmitterId = transmitterId;
+        return (int) (ms_since / 1000L);
+    }
+
+    public static long fromDexTimeCached(int dexTimeStamp) {
+        return fromDexTime(lastTransmitterId, dexTimeStamp);
+    }
+
+
+    public static long fromDexTime(String transmitterId, int dexTimeStamp) {
+        if ((transmitterId == null) || (transmitterId.length() != 6)) {
+            UserError.Log.e(TAG, "Invalid dex transmitter in fromDexTime: " + transmitterId);
+            return -3;
+        }
+        lastTransmitterId = transmitterId;
+        final long transmitter_start_timestamp = PersistentStore.getLong(DEX_XMIT_START + transmitterId);
+        if (transmitter_start_timestamp > 0) {
+            return transmitter_start_timestamp + (((long) dexTimeStamp) * 1000L);
+        } else {
+            return -1;
+        }
+
+    }
+
+    // should we try to use this transmitter
+    public static boolean isInDate(String transmitterId) {
+        final int valid_time = getDexTime(transmitterId, JoH.tsl());
+        return (valid_time >= 0) && (valid_time < DEX_TRANSMITTER_LIFE_SECONDS);
+    }
+
+    public static int getTransmitterAgeInDays(final String transmitterId) {
+        final int valid_time = getDexTime(transmitterId, JoH.tsl());
+        return (valid_time >= 0) ? valid_time / 86400 : -1;
+    }
+
+    public static String extractForStream(String transmitterId) {
+        if (transmitterId == null || transmitterId.length() == 0) return null;
+        final long result = PersistentStore.getLong(DEX_XMIT_START + transmitterId);
+        if (result == 0) return null;
+        return transmitterId + "^" + result;
+    }
+
+    public static void injectFromStream(String stream) {
+        if (stream == null) return;
+        final String[] components = stream.split("\\^");
+        try {
+            if (components.length == 2) {
+                final long time_stamp = Long.parseLong(components[1]);
+                if (time_stamp > OLDEST_ALLOWED) {
+                    PersistentStore.setLong(DEX_XMIT_START + components[0], time_stamp);
+                    UserError.Log.d(TAG, "Updating time keeper: " + components[0] + " " + JoH.dateTimeText(time_stamp));
+                } else {
+                    UserError.Log.wtf(TAG, "Dex Timestamp doesn't meet criteria: " + time_stamp);
+                }
+            } else {
+                UserError.Log.e(TAG, "Invalid injectFromStream length: " + stream);
+            }
+        } catch (NumberFormatException e) {
+            UserError.Log.e(TAG, "Invalid injectFromStream: " + stream + " " + e);
+        }
+    }
+
+
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/DisconnectTxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/DisconnectTxMessage.java
@@ -0,0 +1,21 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import com.eveningoutpost.dexdrip.Models.JoH;
+
+import java.nio.ByteBuffer;
+
+/**
+ * Created by joeginley on 3/16/16.
+ */
+public class DisconnectTxMessage extends BaseMessage {
+    byte opcode = 0x09;
+    private final static String TAG = G5CollectionService.TAG; // meh
+    public DisconnectTxMessage() {
+        data = ByteBuffer.allocate(1);
+        data.put(opcode);
+
+        byteSequence = data.array();
+        UserError.Log.d(TAG,"DisconnectTX: "+ JoH.bytesToHex(byteSequence));
+    }
+}
+
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/EGlucoseRxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/EGlucoseRxMessage.java
@@ -0,0 +1,60 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+
+import com.eveningoutpost.dexdrip.Models.JoH;
+import com.eveningoutpost.dexdrip.Models.UserError;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+
+public class EGlucoseRxMessage extends BaseGlucoseRxMessage {
+
+    private static final String TAG = EGlucoseRxMessage.class.getSimpleName();
+
+    private Integer predicted_glucose; // : UInt16
+    public static final byte opcode = 0x4f;
+
+    public EGlucoseRxMessage(byte[] packet) {
+        UserError.Log.d(TAG, "EGlucoseRX dbg: " + JoH.bytesToHex(packet));
+        if (packet.length >= 14) {
+            data = ByteBuffer.wrap(packet).order(ByteOrder.LITTLE_ENDIAN);
+            if ((data.get() == opcode) && checkCRC(packet)) {
+
+
+                //status_raw = data.get();
+                status = TransmitterStatus.getBatteryLevel(data.get()); // ??
+                sequence = data.getInt();
+                timestamp = data.getInt();
+
+
+                int glucoseBytes = data.getShort(); // check signed vs unsigned!!
+                glucoseIsDisplayOnly = (glucoseBytes & 0xf000) > 0;
+                glucose = glucoseBytes & 0xfff;
+
+                state = data.get();
+                trend = data.get();
+
+                if (glucose > 13) {
+                    unfiltered = glucose * 1000;
+                    filtered = glucose * 1000;
+                } else {
+                    filtered = glucose;
+                    unfiltered = glucose;
+                }
+
+                predicted_glucose = data.getShort() & 0x03ff; // needs mask??? // remaining bits??
+
+                UserError.Log.d(TAG, "EGlucoseRX: seq:" + sequence + " ts:" + timestamp + " sg:" + glucose + " psg: " + predicted_glucose + " do:" + glucoseIsDisplayOnly + " ss:" + status + " sr:" + status_raw + " st:" + CalibrationState.parse(state) + " tr:" + getTrend());
+
+            }
+        } else {
+            UserError.Log.d(TAG, "GlucoseRxMessage packet length received wrong: " + packet.length);
+        }
+
+    }
+
+    @Override
+    public Integer getPredictedGlucose() {
+        return predicted_glucose;
+    }
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/EGlucoseTxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/EGlucoseTxMessage.java
@@ -0,0 +1,19 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+
+// created by jamorham
+
+
+public class EGlucoseTxMessage extends BaseMessage {
+
+    final byte opcode = 0x4e;
+
+    public EGlucoseTxMessage() {
+        data = ByteBuffer.allocate(3).order(ByteOrder.LITTLE_ENDIAN);
+        data.put(opcode);
+        appendCRC();
+    }
+
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/Extensions.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/Extensions.java
@@ -0,0 +1,39 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+/**
+ * Created by joeginley on 3/19/16.
+ */
+public class Extensions {
+
+    public static String bytesToHex(byte[] in) {
+        final StringBuilder builder = new StringBuilder();
+        for(byte b : in) {
+            builder.append(String.format("%02x", b));
+        }
+        return builder.toString();
+    }
+
+    public static byte[] hexToBytes(String s) {
+        int len = s.length();
+        byte[] data = new byte[len / 2];
+        for (int i = 0; i < len; i += 2) {
+            data[i / 2] = (byte) ((Character.digit(s.charAt(i), 16) << 4)
+                    + Character.digit(s.charAt(i+1), 16));
+        }
+        return data;
+    }
+
+    public static String lastTwoCharactersOfString(final String s) {
+        if (s == null) return "NULL";
+        return s.length() > 1 ? s.substring(s.length() - 2) : "ERR-" + s;
+    }
+
+    public static void doSleep(long time) {
+        try {
+            Thread.sleep(time);
+        } catch (InterruptedException e) {
+            e.printStackTrace();
+        }
+    }
+
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/F2DUnknownRxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/F2DUnknownRxMessage.java
@@ -0,0 +1,12 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+// jamorham
+
+public class F2DUnknownRxMessage extends BaseMessage {
+
+    public static final byte opcode = (byte) 0xD0;
+
+    public F2DUnknownRxMessage(final byte[] packet) {
+        // stub
+    }
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/FastCRC16.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/FastCRC16.java
@@ -0,0 +1,26 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+// jamorham
+
+public class FastCRC16 {
+
+    private static final int table[] = {0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50a5, 0x60c6, 0x70e7, 0x8108, 0x9129, 0xa14a, 0xb16b, 0xc18c, 0xd1ad, 0xe1ce, 0xf1ef, 0x1231, 0x0210, 0x3273, 0x2252, 0x52b5, 0x4294, 0x72f7, 0x62d6, 0x9339, 0x8318, 0xb37b, 0xa35a, 0xd3bd, 0xc39c, 0xf3ff, 0xe3de, 0x2462, 0x3443, 0x0420, 0x1401, 0x64e6, 0x74c7, 0x44a4, 0x5485, 0xa56a, 0xb54b, 0x8528, 0x9509, 0xe5ee, 0xf5cf, 0xc5ac, 0xd58d, 0x3653, 0x2672, 0x1611, 0x0630, 0x76d7, 0x66f6, 0x5695, 0x46b4, 0xb75b, 0xa77a, 0x9719, 0x8738, 0xf7df, 0xe7fe, 0xd79d, 0xc7bc, 0x48c4, 0x58e5, 0x6886, 0x78a7, 0x0840, 0x1861, 0x2802, 0x3823, 0xc9cc, 0xd9ed, 0xe98e, 0xf9af, 0x8948, 0x9969, 0xa90a, 0xb92b, 0x5af5, 0x4ad4, 0x7ab7, 0x6a96, 0x1a71, 0x0a50, 0x3a33, 0x2a12, 0xdbfd, 0xcbdc, 0xfbbf, 0xeb9e, 0x9b79, 0x8b58, 0xbb3b, 0xab1a, 0x6ca6, 0x7c87, 0x4ce4, 0x5cc5, 0x2c22, 0x3c03, 0x0c60, 0x1c41, 0xedae, 0xfd8f, 0xcdec, 0xddcd, 0xad2a, 0xbd0b, 0x8d68, 0x9d49, 0x7e97, 0x6eb6, 0x5ed5, 0x4ef4, 0x3e13, 0x2e32, 0x1e51, 0x0e70, 0xff9f, 0xefbe, 0xdfdd, 0xcffc, 0xbf1b, 0xaf3a, 0x9f59, 0x8f78, 0x9188, 0x81a9, 0xb1ca, 0xa1eb, 0xd10c, 0xc12d, 0xf14e, 0xe16f, 0x1080, 0x00a1, 0x30c2, 0x20e3, 0x5004, 0x4025, 0x7046, 0x6067, 0x83b9, 0x9398, 0xa3fb, 0xb3da, 0xc33d, 0xd31c, 0xe37f, 0xf35e, 0x02b1, 0x1290, 0x22f3, 0x32d2, 0x4235, 0x5214, 0x6277, 0x7256, 0xb5ea, 0xa5cb, 0x95a8, 0x8589, 0xf56e, 0xe54f, 0xd52c, 0xc50d, 0x34e2, 0x24c3, 0x14a0, 0x0481, 0x7466, 0x6447, 0x5424, 0x4405, 0xa7db, 0xb7fa, 0x8799, 0x97b8, 0xe75f, 0xf77e, 0xc71d, 0xd73c, 0x26d3, 0x36f2, 0x0691, 0x16b0, 0x6657, 0x7676, 0x4615, 0x5634, 0xd94c, 0xc96d, 0xf90e, 0xe92f, 0x99c8, 0x89e9, 0xb98a, 0xa9ab, 0x5844, 0x4865, 0x7806, 0x6827, 0x18c0, 0x08e1, 0x3882, 0x28a3, 0xcb7d, 0xdb5c, 0xeb3f, 0xfb1e, 0x8bf9, 0x9bd8, 0xabbb, 0xbb9a, 0x4a75, 0x5a54, 0x6a37, 0x7a16, 0x0af1, 0x1ad0, 0x2ab3, 0x3a92, 0xfd2e, 0xed0f, 0xdd6c, 0xcd4d, 0xbdaa, 0xad8b, 0x9de8, 0x8dc9, 0x7c26, 0x6c07, 0x5c64, 0x4c45, 0x3ca2, 0x2c83, 0x1ce0, 0x0cc1, 0xef1f, 0xff3e, 0xcf5d, 0xdf7c, 0xaf9b, 0xbfba, 0x8fd9, 0x9ff8, 0x6e17, 0x7e36, 0x4e55, 0x5e74, 0x2e93, 0x3eb2, 0x0ed1, 0x1ef0, 0x8616};
+
+    public static byte[] calculate(final byte b) {
+        final int crc = table[b & 0xff];
+        return new byte[]{(byte) (crc & 0xff), (byte) ((crc >> 8) & 0xff)};
+    }
+
+    public static byte[] calculate(final byte[] bytes, int end) {
+        int crc = 0;
+        for (int i = 0; i < end; i++) {
+            crc = (crc << 8) ^ table[(crc >>> 8 ^ bytes[i]) & 0xff];
+        }
+        return new byte[]{(byte) (crc & 0xff), (byte) ((crc >> 8) & 0xff)};
+    }
+
+    public static byte[] calculate(final byte[] bytes) {
+        return calculate(bytes, bytes.length);
+    }
+
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/FirmwareCapability.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/FirmwareCapability.java
@@ -0,0 +1,100 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+// jamorham
+
+import com.eveningoutpost.dexdrip.UtilityModels.Constants;
+import com.google.common.collect.ImmutableSet;
+
+import static com.eveningoutpost.dexdrip.G5Model.Ob1G5StateMachine.getRawFirmwareVersionString;
+
+public class FirmwareCapability {
+
+    private static final ImmutableSet<String> KNOWN_G5_FIRMWARES = ImmutableSet.of("1.0.0.13", "1.0.0.17", "1.0.4.10", "1.0.4.12");
+    private static final ImmutableSet<String> KNOWN_G6_FIRMWARES = ImmutableSet.of("1.6.5.23", "1.6.5.25", "1.6.5.27");
+    private static final ImmutableSet<String> KNOWN_G6_REV2_FIRMWARES = ImmutableSet.of("2.18.2.67", "2.18.2.88", "2.18.2.98");
+    private static final ImmutableSet<String> KNOWN_G6_REV2_RAW_FIRMWARES = ImmutableSet.of("2.18.2.67");
+    private static final ImmutableSet<String> KNOWN_G6_PLUS_FIRMWARES = ImmutableSet.of("2.4.2.88");
+    private static final ImmutableSet<String> KNOWN_TIME_TRAVEL_TESTED = ImmutableSet.of("1.6.5.25");
+
+    // new G6 firmware versions will need to be added here / above
+    static boolean isG6Firmware(final String version) {
+        return version != null && (KNOWN_G6_FIRMWARES.contains(version)
+                || KNOWN_G6_REV2_FIRMWARES.contains(version)
+                || KNOWN_G6_PLUS_FIRMWARES.contains(version)
+                || version.startsWith("1.6.5.")
+                || version.startsWith("2.18.")
+                || version.startsWith("2.4."));
+    }
+
+    public static boolean isG6Rev2(final String version) {
+        return version != null && (KNOWN_G6_REV2_FIRMWARES.contains(version) || version.startsWith("2.18."));
+    }
+
+    public static boolean isG6Plus(final String version) {
+        return version != null && (KNOWN_G6_PLUS_FIRMWARES.contains(version) || version.startsWith("2.4."));
+    }
+
+    static boolean isG5Firmware(final String version) {
+        return KNOWN_G5_FIRMWARES.contains(version);
+    }
+
+    static boolean isFirmwareTimeTravelCapable(final String version) {
+        return KNOWN_TIME_TRAVEL_TESTED.contains(version);
+    }
+
+    public static boolean isFirmwareTemperatureCapable(final String version) {
+        return !isG6Rev2(version) && !isG6Plus(version);
+    }
+
+    private static boolean isFirmwarePredictiveCapable(final String version) {
+        return isG6Firmware(version);
+    }
+
+    static boolean isFirmwareRawCapable(final String version) {
+        return version == null
+                || version.equals("")
+                || KNOWN_G5_FIRMWARES.contains(version)
+                || KNOWN_G6_FIRMWARES.contains(version)
+                || KNOWN_G6_REV2_RAW_FIRMWARES.contains(version);
+    }
+
+    static boolean isFirmwarePreemptiveRestartCapable(final String version) {
+        return isFirmwareRawCapable(version); // hang off this for now as they are currently the same
+    }
+
+    public static boolean isTransmitterPredictiveCapable(final String tx_id) {
+        return isG6Firmware(getRawFirmwareVersionString(tx_id));
+    }
+
+    public static boolean isTransmitterG5(final String tx_id) {
+        return isG5Firmware(getRawFirmwareVersionString(tx_id));
+    }
+
+    public static boolean isTransmitterG6(final String tx_id) {
+        return isG6Firmware(getRawFirmwareVersionString(tx_id));
+    }
+
+    public static boolean isTransmitterG6Rev2(final String tx_id) {
+        return isG6Rev2(getRawFirmwareVersionString(tx_id));
+    }
+
+    public static boolean isTransmitterTimeTravelCapable(final String tx_id) {
+        return isFirmwareTimeTravelCapable(getRawFirmwareVersionString(tx_id));
+    }
+
+    public static boolean isTransmitterRawCapable(final String tx_id) {
+        return isFirmwareRawCapable(getRawFirmwareVersionString(tx_id));
+    }
+
+    public static boolean isTransmitterPreemptiveRestartCapable(final String tx_id) {
+        return isFirmwarePreemptiveRestartCapable(getRawFirmwareVersionString(tx_id));
+    }
+
+    static long getWarmupPeriodForVersion(final String version) {
+        return isG6Plus(version) ? Constants.HOUR_IN_MS : Constants.HOUR_IN_MS * 2;
+    }
+
+    public static long getWarmupPeriod(final String tx_id) {
+        return getWarmupPeriod(getRawFirmwareVersionString(tx_id));
+    }
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/G6CalibrationParameters.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/G6CalibrationParameters.java
@@ -0,0 +1,140 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import com.eveningoutpost.dexdrip.UtilityModels.PersistentStore;
+
+import lombok.Getter;
+
+public class G6CalibrationParameters {
+
+    public static final String PREF_CURRENT_CODE = "G6-Current-Sensor-Code";
+
+    @Getter
+    private final String code;
+    @Getter
+    private final int paramA;
+    @Getter
+    private final int paramB;
+
+
+    public G6CalibrationParameters(String code) {
+
+        this.code = code;
+
+        switch (code) {
+
+            // special null code
+            case "0000":
+                paramA = 1;
+                paramB = 0;
+                break;
+
+            case "5915":
+                paramA = 3100;
+                paramB = 3600;
+                break;
+
+            case "5917":
+                paramA = 3000;
+                paramB = 3500;
+                break;
+
+            case "5931":
+                paramA = 2900;
+                paramB = 3400;
+                break;
+
+            case "5937":
+                paramA = 2800;
+                paramB = 3300;
+                break;
+
+            case "5951":
+                paramA = 3100;
+                paramB = 3500;
+                break;
+
+            case "5955":
+                paramA = 3000;
+                paramB = 3400;
+                break;
+
+            case "7171":
+                paramA = 2700;
+                paramB = 3300;
+                break;
+
+            case "9117":
+                paramA = 2700;
+                paramB = 3200;
+                break;
+
+            case "9159":
+                paramA = 2600;
+                paramB = 3200;
+                break;
+
+            case "9311":
+                paramA = 2600;
+                paramB = 3100;
+                break;
+
+            case "9371":
+                paramA = 2500;
+                paramB = 3100;
+                break;
+
+            case "9515":
+                paramA = 2500;
+                paramB = 3000;
+                break;
+
+            case "9551":
+                paramA = 2400;
+                paramB = 3000;
+                break;
+
+            case "9577":
+                paramA = 2400;
+                paramB = 2900;
+                break;
+
+            case "9713":
+                paramA = 2300;
+                paramB = 2900;
+                break;
+
+            default:
+                paramA = -1;
+                paramB = -1;
+        }
+
+    }
+
+    public boolean isValid() {
+        return paramA > 0;
+    }
+
+    public boolean isNullCode() {
+        return isValid() && paramB == 0;
+    }
+
+    public static boolean checkCode(String code) {
+        return new G6CalibrationParameters(code).isValid();
+    }
+
+    public static String getCurrentSensorCode() {
+        final String code = PersistentStore.getString(PREF_CURRENT_CODE);
+        return code.equals("") ? null : code;
+    }
+
+    public static void setCurrentSensorCode(String code) {
+        if (checkCode(code)) {
+            PersistentStore.setString(PREF_CURRENT_CODE, code);
+        } else {
+            PersistentStore.setString(PREF_CURRENT_CODE, "");
+            throw new RuntimeException("Invalid sensor code: " + code);
+        }
+    }
+
+
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/GlucoseRxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/GlucoseRxMessage.java
@@ -0,0 +1,64 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import com.eveningoutpost.dexdrip.Models.JoH;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+
+import lombok.NoArgsConstructor;
+
+/**
+ * Created by jamorham on 25/11/2016.
+ *
+ * Alternate mechanism for reading data using the transmitter's internal algorithm.
+ *
+ * initial packet structure cribbed from Loopkit
+ */
+
+@NoArgsConstructor
+public class GlucoseRxMessage extends BaseGlucoseRxMessage {
+
+    private final static String TAG = G5CollectionService.TAG; // meh
+
+    public static final byte opcode = 0x31;
+
+
+    public GlucoseRxMessage(byte[] packet) {
+        UserError.Log.d(TAG, "GlucoseRX dbg: " + JoH.bytesToHex(packet));
+        if (packet.length >= 14) {
+            data = ByteBuffer.wrap(packet).order(ByteOrder.LITTLE_ENDIAN);
+            if ((data.get() == opcode) && checkCRC(packet)) {
+
+                data = ByteBuffer.wrap(packet).order(ByteOrder.LITTLE_ENDIAN);
+
+                status_raw = data.get(1);
+                status = TransmitterStatus.getBatteryLevel(data.get(1));
+                sequence = data.getInt(2);
+                timestamp = data.getInt(6);
+
+
+                int glucoseBytes = data.getShort(10); // check signed vs unsigned!!
+                glucoseIsDisplayOnly = (glucoseBytes & 0xf000) > 0;
+                glucose = glucoseBytes & 0xfff;
+
+                state = data.get(12);
+                trend = data.get(13);
+                if (glucose > 13) {
+                    unfiltered = glucose * 1000;
+                    filtered = glucose * 1000;
+                } else {
+                    filtered = glucose;
+                    unfiltered = glucose;
+                }
+
+                UserError.Log.d(TAG, "GlucoseRX: seq:" + sequence + " ts:" + timestamp + " sg:" + glucose + " do:" + glucoseIsDisplayOnly + " ss:" + status + " sr:" + status_raw + " st:" + CalibrationState.parse(state) + " tr:" + getTrend());
+
+            }
+        } else {
+            UserError.Log.d(TAG, "GlucoseRxMessage packet length received wrong: " + packet.length);
+        }
+
+    }
+
+
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/GlucoseTxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/GlucoseTxMessage.java
@@ -0,0 +1,20 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import com.eveningoutpost.dexdrip.Models.JoH;
+
+
+/**
+ * Created by jamorham on 25/11/2016.
+ */
+
+public class GlucoseTxMessage extends BaseMessage {
+
+    private final static String TAG = G5CollectionService.TAG; // meh
+    static final byte opcode = 0x30;
+
+    public GlucoseTxMessage() {
+        init(opcode, 3);
+        UserError.Log.d(TAG, "GlucoseTx dbg: " + JoH.bytesToHex(byteSequence));
+    }
+}
+
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/InvalidRxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/InvalidRxMessage.java
@@ -0,0 +1,20 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+// jamorham
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+
+public class InvalidRxMessage extends BaseMessage {
+
+    public static final byte opcode = (byte) 0xFF;
+    private static final int length = 3;
+
+    InvalidRxMessage(byte[] packet) {
+
+        if ((packet.length == length) && packet[0] == opcode) {
+            data = ByteBuffer.wrap(packet).order(ByteOrder.LITTLE_ENDIAN);
+        }
+    }
+
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/KeepAliveTxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/KeepAliveTxMessage.java
@@ -0,0 +1,29 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import com.eveningoutpost.dexdrip.Models.JoH;
+import com.eveningoutpost.dexdrip.Models.UserError;
+import com.eveningoutpost.dexdrip.Services.G5CollectionService;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+
+/**
+ * Created by joeginley on 3/16/16.
+ */
+public class KeepAliveTxMessage extends BaseMessage {
+    public static final int opcode = 0x06;
+    private int time;
+
+    private final static String TAG = G5CollectionService.TAG; // meh
+
+    public KeepAliveTxMessage(int time) {
+        this.time = time;
+
+        data = ByteBuffer.allocate(2);
+        data.put(new byte[]{(byte) opcode, (byte) this.time});
+        byteSequence = data.order(ByteOrder.LITTLE_ENDIAN).array();
+
+        UserError.Log.d(TAG, "New KeepAliveRequestTxMessage: " + JoH.bytesToHex(byteSequence));
+
+    }
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/Ob1G5StateMachine.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/Ob1G5StateMachine.java
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/Ob1Work.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/Ob1Work.java
@@ -0,0 +1,33 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import com.eveningoutpost.dexdrip.Models.JoH;
+import com.google.common.collect.ImmutableSet;
+import com.google.gson.annotations.Expose;
+
+/**
+ * Created by jamorham on 12/10/2017.
+ */
+
+public class Ob1Work {
+
+    private static final ImmutableSet<Class> streamClasses = ImmutableSet.of(SessionStartTxMessage.class, SessionStopTxMessage.class, CalibrateTxMessage.class);
+
+    @Expose
+    public final BaseMessage msg;
+    @Expose
+    public final String text;
+    @Expose
+    public final long timestamp;
+    public volatile int retry = 0;
+
+    Ob1Work(BaseMessage msg, String text) {
+        this.msg = msg;
+        this.text = text;
+        this.timestamp = JoH.tsl();
+    }
+
+    public boolean streamable() {
+        return streamClasses.contains(msg.getClass());
+    }
+
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/RawScaling.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/RawScaling.java
@@ -0,0 +1,36 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+// jamorham
+
+import static com.eveningoutpost.dexdrip.G5Model.Ob1G5StateMachine.usingG6;
+
+public class RawScaling {
+
+    public enum DType {
+        G5, G6v1, G6v2
+    }
+
+    public static double scale(final long raw, final DType version, final boolean filtered) {
+        switch (version) {
+            case G6v1:
+                return raw * 34;
+            case G6v2:
+                return (raw - 1151500000) / 110;
+            default:
+                return raw;
+        }
+    }
+
+    public static double scale(final long raw, final String transmitter_id, final boolean filtered) {
+        final boolean g6 = usingG6();
+
+        if (!g6) {
+            return scale(raw, DType.G5, filtered);
+        } else {
+            final boolean g6r2 = FirmwareCapability.isTransmitterG6Rev2(transmitter_id);
+            return scale(raw, g6r2 ? DType.G6v2 : DType.G6v1, filtered);
+        }
+
+    }
+
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/ResetTxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/ResetTxMessage.java
@@ -0,0 +1,15 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import com.eveningoutpost.dexdrip.Models.JoH;
+import com.eveningoutpost.dexdrip.Models.UserError;
+
+// jamorham
+
+class ResetTxMessage extends BaseMessage {
+    static final byte opcode = 0x42;
+
+    ResetTxMessage() {
+        init(opcode, 3);
+        UserError.Log.d(TAG, "ResetTx dbg: " + JoH.bytesToHex(byteSequence));
+    }
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/SensorDays.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/SensorDays.java
@@ -0,0 +1,202 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+
+import android.text.SpannableString;
+
+import com.eveningoutpost.dexdrip.Models.Sensor;
+import com.eveningoutpost.dexdrip.R;
+import com.eveningoutpost.dexdrip.UtilityModels.Constants;
+import com.eveningoutpost.dexdrip.UtilityModels.Pref;
+import com.eveningoutpost.dexdrip.UtilityModels.StatusItem.Highlight;
+import com.eveningoutpost.dexdrip.ui.helpers.Span;
+import com.eveningoutpost.dexdrip.utils.DexCollectionType;
+import com.eveningoutpost.dexdrip.xdrip;
+
+import java.text.MessageFormat;
+import java.text.SimpleDateFormat;
+import java.util.HashMap;
+import java.util.Locale;
+
+import lombok.Getter;
+import lombok.val;
+
+import static com.eveningoutpost.dexdrip.G5Model.Ob1G5StateMachine.getFirmwareXDetails;
+import static com.eveningoutpost.dexdrip.Models.JoH.msSince;
+import static com.eveningoutpost.dexdrip.Models.JoH.roundDouble;
+import static com.eveningoutpost.dexdrip.Models.JoH.tsl;
+import static com.eveningoutpost.dexdrip.Services.G5BaseService.usingG6;
+import static com.eveningoutpost.dexdrip.Services.Ob1G5CollectionService.getTransmitterID;
+import static com.eveningoutpost.dexdrip.Services.Ob1G5CollectionService.usingNativeMode;
+import static com.eveningoutpost.dexdrip.UtilityModels.Constants.DAY_IN_MS;
+import static com.eveningoutpost.dexdrip.utils.DexCollectionType.getDexCollectionType;
+import static com.eveningoutpost.dexdrip.utils.DexCollectionType.hasDexcomRaw;
+import static com.eveningoutpost.dexdrip.utils.DexCollectionType.hasLibre;
+
+// jamorham
+
+// helper class to deal with sensor expiry
+
+public class SensorDays {
+
+    private static final String TAG = "SensorDays";
+
+    private static final long UNKNOWN = -1;
+    private static final int USE_DEXCOM_STRATEGY = 5;
+    private static final int USE_LIBRE_STRATEGY = 6;
+
+    private static final long CAL_THRESHOLD1 = DAY_IN_MS * 4;
+    private static final long CAL_THRESHOLD2 = Constants.HOUR_IN_MS * 18;
+
+    private static final HashMap<String, SensorDays> cache = new HashMap<>();
+
+    @Getter
+    private long period = UNKNOWN;
+    private long created = 0;
+    private int strategy = 0;
+
+    // load current config and compute
+    public static SensorDays get() {
+        val type = getDexCollectionType();
+        val tx_id = getTransmitterID();
+        return get(type, tx_id);
+    }
+
+    // compute based on type
+    public static SensorDays get(final DexCollectionType type, final String tx_id) {
+
+        // get cached result
+        val result = cache.get(type.toString() + tx_id);
+        if (result != null && result.cacheValid()) return result;
+
+        val ths = new SensorDays();
+
+        if (hasLibre(type)) {
+            ths.period = Constants.DAY_IN_MS * 14; // TODO 10 day sensors?
+            ths.strategy = USE_LIBRE_STRATEGY;
+
+        } else if (hasDexcomRaw(type)) {
+            ths.strategy = USE_DEXCOM_STRATEGY;
+            val vr2 = (VersionRequest2RxMessage)
+                    getFirmwareXDetails(tx_id, 2);
+            if (vr2 != null) {
+                ths.period = Constants.DAY_IN_MS * vr2.typicalSensorDays;
+            } else {
+                if (usingG6()) {
+                    ths.period = Constants.DAY_IN_MS * 10; // G6 default
+                } else {
+                    ths.period = Constants.DAY_IN_MS * 7; // G5
+                }
+            }
+
+        } else {
+            // unknown type
+        }
+        ths.created = tsl();
+        cache.put(type.toString() + tx_id, ths);
+        return ths;
+    }
+
+    private long getDexcomStart() {
+        if (usingNativeMode()) {
+            return DexSessionKeeper.getStart();
+        } else {
+            try {
+                // In non-native mode the expiration is a guide only
+                return Sensor.currentSensor().started_at;
+            } catch (Exception e) {
+                return -1;
+            }
+        }
+    }
+
+    private long getLibreStart() {
+        try {
+            val age_minutes = Pref.getInt("nfc_sensor_age", -50000);
+            if (age_minutes > 0) {
+                return tsl() - (age_minutes * Constants.MINUTE_IN_MS);
+            } else {
+                return Sensor.currentSensor().started_at;
+            }
+        } catch (Exception e) {
+            return -1;
+        }
+    }
+
+    private long getStart() {
+        switch (strategy) {
+            case USE_DEXCOM_STRATEGY:
+                return getDexcomStart();
+            case USE_LIBRE_STRATEGY:
+                return getLibreStart();
+            default:
+                return 0; // very large error default will be caught by sanity check
+        }
+    }
+
+    private boolean isStarted() {
+        return getStart() > 0;
+    }
+
+    // returns 0 if invalid
+    long getRemainingSensorPeriodInMs() {
+        //UserError.Log.d(TAG, "Get start debug returns: " + JoH.dateTimeText(getStart()));
+        if (isValid()) {
+            val elapsed = msSince(getStart());
+            long remaining = period - elapsed;
+            // sanity check
+            if ((remaining < 0) || (remaining > period)) {
+                remaining = 0;
+            }
+            return remaining;
+        } else {
+            return 0;
+        }
+    }
+
+    long getSensorEndTimestamp() {
+        if (isValid()) {
+            return getStart() + period;
+        } else {
+            return 0;
+        }
+    }
+
+    // Add resolution / update cache
+    public SpannableString getSpannable() {
+
+        val expiryMs = getRemainingSensorPeriodInMs();
+
+        if (expiryMs > 0) {
+            if (expiryMs > CAL_THRESHOLD1) {
+                val fmt = xdrip.gs(R.string.expires_days);
+                return new SpannableString(MessageFormat.format(fmt, roundDouble((double) expiryMs / DAY_IN_MS, 1)));
+            } else {
+                // expiring soon
+                val niceTime = new SimpleDateFormat(expiryMs < CAL_THRESHOLD2 ? "h:mm a" : "EEE, h:mm a", Locale.getDefault()).format(getSensorEndTimestamp());
+                return Span.colorSpan(MessageFormat.format(xdrip.gs(R.string.expires_at), niceTime), expiryMs < CAL_THRESHOLD2 ? Highlight.BAD.color() : Highlight.NOTICE.color());
+            }
+        }
+        return new SpannableString("");
+    }
+
+    public boolean isValid() {
+        return isKnown() && isSessionLive() && isStarted();
+    }
+
+    private boolean isSessionLive() {
+        return Sensor.isActive();
+    }
+
+    boolean isKnown() {
+        return period != UNKNOWN;
+    }
+
+    boolean cacheValid() {
+        return msSince(created) < Constants.MINUTE_IN_MS * 10;
+    }
+
+    void invalidateCache() {
+        created = -1;
+    }
+
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/SensorRxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/SensorRxMessage.java
@@ -0,0 +1,33 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import com.eveningoutpost.dexdrip.Models.JoH;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+
+/**
+ * Created by jcostik1 on 3/26/16.
+ */
+public class SensorRxMessage extends BaseMessage {
+    public static final byte opcode = 0x2f;
+    public TransmitterStatus status;
+    public int timestamp;
+    public int unfiltered;
+    public int filtered;
+    private final static String TAG = G5CollectionService.TAG; // meh
+
+    public SensorRxMessage(byte[] packet) {
+        UserError.Log.d(TAG, "SensorRX dbg: " + JoH.bytesToHex(packet));
+        if (packet.length >= 14) {
+            if (packet[0] == opcode) {
+                data = ByteBuffer.wrap(packet).order(ByteOrder.LITTLE_ENDIAN);
+
+                status = TransmitterStatus.getBatteryLevel(data.get(1));
+                timestamp = data.getInt(2);
+
+                unfiltered = data.getInt(6);
+                filtered = data.getInt(10);
+            }
+        }
+    }
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/SensorTxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/SensorTxMessage.java
@@ -0,0 +1,23 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import com.eveningoutpost.dexdrip.Models.JoH;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+
+/**
+ * Created by jcostik1 on 3/26/16.
+ */
+public class SensorTxMessage extends BaseMessage {
+    byte opcode = 0x2e;
+    byte[] crc = CRC.calculate(opcode);
+
+
+    public SensorTxMessage() {
+        data = ByteBuffer.allocate(3);
+        data.put(opcode);
+        data.put(crc);
+        byteSequence = data.array();
+        UserError.Log.d(TAG, "SensorTx dbg: " + JoH.bytesToHex(byteSequence));
+    }
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/SessionStartRxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/SessionStartRxMessage.java
@@ -0,0 +1,90 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+
+// created by jamorham
+
+public class SessionStartRxMessage extends BaseMessage {
+    public static final byte opcode = 0x27;
+    final byte length = 17;
+
+    private byte status = (byte) 0xFF;
+    private byte info = (byte) 0xFF;
+    final String transmitterId;
+    int sessionStartTime = 0;
+    int requestedStartTime = 0;
+    int transitterTime = 0;
+
+    boolean valid = false;
+
+    public SessionStartRxMessage(byte[] packet, String transmitterId) {
+        this.transmitterId = transmitterId;
+        if (packet.length == length) {
+            data = ByteBuffer.wrap(packet).order(ByteOrder.LITTLE_ENDIAN);
+            if ((data.get() == opcode) && checkCRC(packet)) {
+                valid = true;
+                status = data.get();
+                info = data.get();
+                requestedStartTime = data.getInt();
+                sessionStartTime = data.getInt();
+                transitterTime = data.getInt();
+            }
+        }
+    }
+
+    boolean isValid() {
+        return valid;
+    }
+
+    boolean isOkay() {
+        return isValid() && status == 0x00 && (info == 0x01 || info == 0x05) && sessionStartTime != INVALID_TIME;
+    }
+
+    // beyond hope?
+    boolean isFubar() {
+        return info == 0x04;
+    }
+
+    long getSessionStart() {
+        if (isOkay() && sessionStartTime > 0) {
+            return DexTimeKeeper.fromDexTime(transmitterId, sessionStartTime);
+        } else {
+            return 0;
+        }
+    }
+
+    long getRequestedStart() {
+        if (isOkay() && requestedStartTime > 0) {
+            return DexTimeKeeper.fromDexTime(transmitterId, requestedStartTime);
+        } else {
+            return 0;
+        }
+    }
+
+    long getTransmitterTime() {
+        if (isOkay() && transitterTime > 0) {
+            return DexTimeKeeper.fromDexTime(transmitterId, transitterTime);
+        } else {
+            return 0;
+        }
+    }
+
+    String message() {
+        switch (info) {
+            case 0x01:
+                return "OK";
+            case 0x02:
+                return "Already started";
+            case 0x03:
+                return "Invalid";
+            case 0x04:
+                return "Clock not synchronized or other error"; // probably
+            case 0x05:
+                return "OK G6"; // probably
+            default:
+                return "Unknown code: " + info;
+        }
+    }
+}
+
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/SessionStartTxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/SessionStartTxMessage.java
@@ -0,0 +1,57 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import com.eveningoutpost.dexdrip.Models.JoH;
+import com.eveningoutpost.dexdrip.Models.UserError;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+
+import lombok.Getter;
+
+// created by jamorham
+
+public class SessionStartTxMessage extends BaseMessage {
+
+    final byte opcode = 0x26;
+    @Getter
+    private final long startTime;
+    @Getter
+    private final int dexTime;
+
+    public SessionStartTxMessage(int dexTime) {
+        this((int) (JoH.tsl() / 1000), dexTime);
+    }
+
+    public SessionStartTxMessage(long startTime, int dexTime) {
+        this(startTime, dexTime, null);
+    }
+
+    public SessionStartTxMessage(long startTime, int dexTime, String code) {
+        this.startTime = startTime;
+        this.dexTime = dexTime;
+        final boolean using_g6 = (code != null);
+        data = ByteBuffer.allocate(code == null || new G6CalibrationParameters(code).isNullCode() ? (using_g6 ? 13 : 11) : 17);
+        data.order(ByteOrder.LITTLE_ENDIAN);
+        data.put(opcode);
+        data.putInt(dexTime);
+        data.putInt((int) (startTime / 1000));
+
+        if (code != null) {
+            final G6CalibrationParameters params = new G6CalibrationParameters(code);
+            if (params.isValid() && !params.isNullCode()) {
+                data.putShort((short) params.getParamA());
+                data.putShort((short) params.getParamB());
+            } else {
+                if (!params.isValid()) {
+                    throw new IllegalArgumentException("Invalid G6 code in SessionStartTxMessage");
+                }
+            }
+        }
+        if (using_g6) {
+            data.putShort((short) 0x0000);
+        }
+        appendCRC();
+        UserError.Log.d(TAG, "SessionStartTxMessage dbg: " + JoH.bytesToHex(byteSequence));
+    }
+
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/SessionStopRxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/SessionStopRxMessage.java
@@ -0,0 +1,61 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+
+import lombok.Getter;
+
+// created by jamorham
+
+public class SessionStopRxMessage extends BaseMessage {
+
+    public static final byte opcode = 0x29;
+    final byte length = 17;
+    @Getter
+    private byte status = (byte)0xFF;
+    private byte received = (byte)0xFF;
+    final String transmitterId;
+    int sessionStartTime=0;
+    int sessionStopTime =0;
+    int transitterTime=0;
+    boolean valid = false;
+
+    public SessionStopRxMessage(byte[] packet,String transmitterId) {
+        this.transmitterId = transmitterId;
+        if (packet.length == length) {
+            data = ByteBuffer.wrap(packet).order(ByteOrder.LITTLE_ENDIAN);
+            if ((data.get() == opcode) && checkCRC(packet)) {
+                valid = true;
+                status = data.get();
+                received = data.get();
+                sessionStopTime = data.getInt();
+                sessionStartTime = data.getInt();
+                transitterTime = data.getInt();
+
+            }
+        }
+    }
+
+    boolean isValid() {
+        return valid;
+    }
+
+    boolean isOkay() {
+        return isValid() && status == 0x00;
+    }
+
+    long getSessionStart() {
+        if (isOkay() && sessionStartTime > 0) {
+            return DexTimeKeeper.fromDexTime(transmitterId, sessionStartTime);
+        } else {
+            return 0;
+        }
+    }
+    long getSessionStop() {
+        if (isOkay() && sessionStopTime > 0) {
+            return DexTimeKeeper.fromDexTime(transmitterId, sessionStopTime);
+        } else {
+            return 0;
+        }
+    }
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/SessionStopTxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/SessionStopTxMessage.java
@@ -0,0 +1,30 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import com.eveningoutpost.dexdrip.Models.JoH;
+
+// created by jamorham
+
+public class SessionStopTxMessage extends BaseMessage {
+
+    final byte opcode = 0x28;
+    final int length = 7;
+    {
+        postExecuteGuardTime = 1000;
+    }
+
+    SessionStopTxMessage(int stopTime) {
+
+        init(opcode, length);
+        data.putInt(stopTime);
+        appendCRC();
+    }
+
+    SessionStopTxMessage(String transmitterId) {
+        final int stopTime = DexTimeKeeper.getDexTime(transmitterId, JoH.tsl());
+        init(opcode, 7);
+        data.putInt(stopTime);
+        appendCRC();
+    }
+
+
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/TimeTxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/TimeTxMessage.java
@@ -0,0 +1,11 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+// jamorham
+
+public class TimeTxMessage extends BaseMessage {
+    public static final byte opcode = 0x24;
+
+    TimeTxMessage() {
+        init(opcode, 3);
+    }
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/Transmitter.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/Transmitter.java
@@ -0,0 +1,16 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+/**
+ * Created by joeginley on 3/19/16.
+ */
+public class Transmitter {
+    public String transmitterId = "";
+
+    public Transmitter(String id) {
+        transmitterId = id;
+    }
+
+    public void authenticate() {
+
+    }
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/TransmitterMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/TransmitterMessage.java
@@ -0,0 +1,67 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import com.eveningoutpost.dexdrip.Models.JoH;
+import com.eveningoutpost.dexdrip.Services.G5CollectionService;
+import com.google.gson.annotations.Expose;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+
+/**
+ * Created by joeginley on 3/16/16.
+ */
+
+public class TransmitterMessage {
+    protected static final String TAG = G5CollectionService.TAG; // meh
+    static final int INVALID_TIME = 0xFFFFFFFF;
+    @Expose
+    long postExecuteGuardTime = 50;
+
+    @Expose
+    public volatile byte[] byteSequence = null;
+    public ByteBuffer data = null;
+
+
+    public void setData() {
+        byte[] newData;
+    }
+
+    static int getUnsignedShort(ByteBuffer data) {
+        return ((data.get() & 0xff) + ((data.get() & 0xff) << 8));
+    }
+
+    static int getUnsignedByte(ByteBuffer data) {
+        return ((data.get() & 0xff));
+    }
+
+    static int getUnixTime() {
+        return (int) (JoH.tsl() / 1000);
+    }
+
+    void init(byte opcode, int length) {
+        data = ByteBuffer.allocate(length);
+        data.order(ByteOrder.LITTLE_ENDIAN);
+        data.put(opcode);
+    }
+
+
+    byte[] appendCRC() {
+        data.put(CRC.calculate(getByteSequence(), 0, byteSequence.length - 2));
+        return getByteSequence();
+    }
+
+    boolean checkCRC(byte[] data) {
+        if ((data == null) || (data.length < 3)) return false;
+        final byte[] crc = CRC.calculate(data, 0, data.length - 2);
+        return crc[0] == data[data.length - 2] && crc[1] == data[data.length - 1];
+    }
+
+    byte[] getByteSequence() {
+        byteSequence = data.array();
+        return byteSequence;
+    }
+
+    long guardTime() {
+        return postExecuteGuardTime;
+    }
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/TransmitterStatus.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/TransmitterStatus.java
@@ -0,0 +1,25 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+/**
+ * Created by joeginley on 3/28/16.
+ */
+public enum TransmitterStatus {
+    UNKNOWN, BRICKED, LOW, OK;
+
+    public static TransmitterStatus getBatteryLevel(int b) {
+        if (b > 0x81) {
+            return BRICKED;
+        }
+        else {
+            if (b == 0x81) {
+                return LOW;
+            }
+            else if (b == 0x00) {
+                return OK;
+            }
+            else {
+                return UNKNOWN;
+            }
+        }
+    }
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/TransmitterTimeRxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/TransmitterTimeRxMessage.java
@@ -0,0 +1,60 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import com.eveningoutpost.dexdrip.Models.JoH;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+
+import lombok.Getter;
+
+/**
+ * Created by joeginley on 3/28/16.
+ */
+public class TransmitterTimeRxMessage extends BaseMessage {
+    public static final byte opcode = 0x25;
+    @Getter
+    private TransmitterStatus status;
+    @Getter
+    private int currentTime;
+    @Getter
+    private int sessionStartTime;
+
+    public TransmitterTimeRxMessage(byte[] packet) {
+        if (packet.length >= 10) {
+            if (packet[0] == opcode && checkCRC(packet)) {
+                data = ByteBuffer.wrap(packet).order(ByteOrder.LITTLE_ENDIAN);
+
+                status = TransmitterStatus.getBatteryLevel(data.get(1));
+                currentTime = data.getInt(2);
+                sessionStartTime = data.getInt(6);
+                // TODO more bytes after this?
+            }
+        }
+    }
+
+    public boolean sessionInProgress() {
+        return sessionStartTime != -1 && currentTime != sessionStartTime;
+    }
+
+    public long getRealSessionStartTime(long now) {
+        return now - ((currentTime - sessionStartTime) * 1000);
+    }
+
+    public long getRealSessionStartTime() {
+
+        if (sessionInProgress()) {
+            return getRealSessionStartTime(JoH.tsl());
+        } else {
+            return -1;
+        }
+    }
+
+    public long getSessionDuration() {
+        if (sessionInProgress()) {
+            return JoH.msSince(getRealSessionStartTime());
+        } else {
+            return -1;
+        }
+    }
+
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/TransmitterTimeTxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/TransmitterTimeTxMessage.java
@@ -0,0 +1,18 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import java.nio.ByteBuffer;
+
+/**
+ * Created by joeginley on 3/28/16.
+ */
+public class TransmitterTimeTxMessage extends TransmitterMessage {
+    public static final byte opcode = 0x24;
+    private final static byte[] crc = CRC.calculate(opcode);
+
+    public TransmitterTimeTxMessage() {
+        data = ByteBuffer.allocate(3);
+        data.put(opcode);
+        data.put(crc);
+        byteSequence = data.array();
+    }
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/UnbondRequestTxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/UnbondRequestTxMessage.java
@@ -0,0 +1,17 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import java.nio.ByteBuffer;
+
+/**
+ * Created by joeginley on 3/16/16.
+ */
+public class UnbondRequestTxMessage extends TransmitterMessage {
+    byte opcode = 0x6;
+
+    public UnbondRequestTxMessage() {
+        data = ByteBuffer.allocate(1);
+        data.put(opcode);
+
+        byteSequence = data.array();
+    }
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/VersionRequest1RxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/VersionRequest1RxMessage.java
@@ -0,0 +1,46 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+import java.util.Locale;
+
+/**
+ * Created by jamorham on 25/11/2016.
+ */
+
+public class VersionRequest1RxMessage extends BaseMessage {
+
+    public static final byte opcode = 0x4B;
+
+    public int status;
+    public String firmware_version_string;
+    public long build_version;
+    public int version_code;
+    public int inactive_days;
+    public int max_inactive_days;
+    public int max_runtime_days;
+
+
+    public VersionRequest1RxMessage(byte[] packet) {
+        if (packet.length >= 18) {
+            // TODO check CRC??
+            data = ByteBuffer.wrap(packet).order(ByteOrder.LITTLE_ENDIAN);
+            if (data.get() == opcode) {
+                status = data.get();
+                firmware_version_string = dottedStringFromData(data, 4);
+                build_version = getUnsignedInt(data);
+                inactive_days = getUnsignedShort(data);
+                version_code = getUnsignedByte(data);
+                max_runtime_days = getUnsignedShort(data);
+                max_inactive_days = getUnsignedShort(data);
+                // crc
+            }
+        }
+    }
+
+    public String toString() {
+        return String.format(Locale.US, "Status: %s / FW version: %s / Version Code: %d / Build: %d / Inactive: %d / Max Inactive: %d / Max Runtime: %d",
+                TransmitterStatus.getBatteryLevel(status).toString(), firmware_version_string, version_code, build_version, inactive_days, max_inactive_days, max_runtime_days);
+    }
+
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/VersionRequest2RxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/VersionRequest2RxMessage.java
@@ -0,0 +1,40 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+import java.util.Locale;
+
+/**
+ * Created by jamorham on 25/11/2016.
+ */
+
+
+public class VersionRequest2RxMessage extends BaseMessage {
+
+    public static final byte opcode = 0x53;
+
+    public int status;
+    public int typicalSensorDays;
+    public int featureBits;
+
+
+    public VersionRequest2RxMessage(byte[] packet) {
+        if (packet.length >= 18) {
+            // TODO check CRC??
+            data = ByteBuffer.wrap(packet).order(ByteOrder.LITTLE_ENDIAN);
+            if (data.get() == opcode) {
+                status = data.get();
+                typicalSensorDays = getUnsignedByte(data);
+                featureBits = getUnsignedShort(data);
+                // 12 more bytes of unknown data
+                // crc
+            }
+        }
+    }
+
+    public String toString() {
+        return String.format(Locale.US, "Status: %s / Typical Days: %d / : Feature Bits %d",
+                TransmitterStatus.getBatteryLevel(status).toString(), typicalSensorDays, featureBits);
+    }
+
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/VersionRequestRxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/VersionRequestRxMessage.java
@@ -0,0 +1,44 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+import java.util.Locale;
+
+/**
+ * Created by jamorham on 25/11/2016.
+ */
+
+
+public class VersionRequestRxMessage extends BaseMessage {
+
+    public static final byte opcode = 0x21;
+
+    public int status;
+    public String firmware_version_string;
+    public String bluetooth_firmware_version_string;
+    public int hardwarev;
+    public String other_firmware_version;
+    public int asic;
+
+
+    public VersionRequestRxMessage(byte[] packet) {
+        if (packet.length >= 18) {
+            // TODO check CRC??
+            data = ByteBuffer.wrap(packet).order(ByteOrder.LITTLE_ENDIAN);
+            if (data.get() == opcode) {
+                status = data.get();
+                firmware_version_string = dottedStringFromData(data, 4);
+                bluetooth_firmware_version_string = dottedStringFromData(data, 4);
+                hardwarev = data.get();
+                other_firmware_version = dottedStringFromData(data, 3);
+                asic = getUnsignedShort(data); // check signed vs unsigned & byte order!!
+            }
+        }
+    }
+
+    public String toString() {
+        return String.format(Locale.US, "Status: %s / Firmware: %s / BT-Firmware: %s / Other-FW: %s / hardwareV: %d / asic: %d",
+                TransmitterStatus.getBatteryLevel(status).toString(), firmware_version_string, bluetooth_firmware_version_string, other_firmware_version, hardwarev, asic);
+    }
+
+}
--- a/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/VersionRequestTxMessage.java
+++ b/lib/nightscout/com/eveningoutpost/dexdrip/G5Model/VersionRequestTxMessage.java
@@ -0,0 +1,38 @@
+package com.eveningoutpost.dexdrip.G5Model;
+
+import com.eveningoutpost.dexdrip.Models.JoH;
+import com.eveningoutpost.dexdrip.Models.UserError;
+
+/**
+ * Created by jamorham on 25/11/2016.
+ */
+
+public class VersionRequestTxMessage extends BaseMessage {
+
+    static final byte opcode0 = 0x20;
+    static final byte opcode1 = 0x4A;
+    static final byte opcode2 = 0x52;
+
+    public VersionRequestTxMessage() {
+        this(0);
+    }
+
+    public VersionRequestTxMessage(final int version) {
+        byte this_opcode = 0;
+        switch (version) {
+            case 0:
+                this_opcode = opcode0;
+                break;
+            case 1:
+                this_opcode = opcode1;
+                break;
+            case 2:
+                this_opcode = opcode2;
+                break;
+
+        }
+        init(this_opcode, 3);
+        UserError.Log.d(TAG, "VersionTx (" + version + ") dbg: " + JoH.bytesToHex(byteSequence));
+    }
+}
+