How do you solve high latency with UDP on mobile devices - android

I am having an issue getting the network latency to be low for my multiplayer shooter game made with Unity. I am using UDP to send player positions from the game client to my amazon server and back to another game client. My game clients are sending 60 byte UDP packets to the amazon server at a rate of 8 packets per second.
When I play the game on two separate iOS devices (iPhone 7 and iPad mini) the network latency is very low and the players are able to see each other move instantly. However, if I run the game on my iPhone 7 and play against another player who is using a samsung galaxy s4 running android, which is a lower powered device, I experience 5 second latency on the android device when receiving player positions from the iOS device. The odd thing is that the iOS device can receive player positions from the android device instantly. The same issue happens when playing on the iPhone 7 against a client on mac, except the iPhone 7 experiences the 5 second latency when receiving player positions from the mac client. The issue also happens when playing on the Samsung Galaxy S4 against a client on mac, where the galaxy s4 experiences the 5 second latency.
I have tried to increase the udp receive buffer size to 16 MB but it didn't change anything.
Here is a sample of my game client code where I send player positions to the amazon server:
void Update(){
// manually constrain rotation because rigidbody constraints don't work
this.transform.rotation = Quaternion.Euler(new Vector3(0, this.transform.rotation.eulerAngles.y, 0));
this.transform.position = new Vector3(this.transform.position.x, boatHeightConstant, this.transform.position.z);
// Speed Boost Handling
if(isSpeedBoosting == true){
tiltFactor = tiltModifier * (VelocityRatio() + 1.0f);
speedBoostTimer += Time.deltaTime;
}
else{
tiltFactor = VelocityRatio() + 1.0f;
}
if(speedBoostTimer >= speedBoostDuration){
isSpeedBoosting = false;
speedBoostTimer = 0f;
endSpeedBoost = true;
}
if(endSpeedBoost == true){
GetComponentInChildren<MainWeapon>().EndFireRateBoost();
endSpeedBoost = false;
}
// Attack Boost Handling
if(isAttackBoosting == true){
attackBoostTimer += Time.deltaTime;
}
if(attackBoostTimer >= attackBoostDuration){
isAttackBoosting = false;
attackBoostTimer = 0f;
endAttackBoost = true;
}
if(endAttackBoost == true){
GetComponentInChildren<MainWeapon>().ResetDamage();
GetComponentInChildren<MainWeapon>().ResetHeatUpRate();
endAttackBoost = false;
}
if (GetComponent<InputManager>().GetInputType() == 0 || GetComponent<InputManager>().GetInputType() == 1 )
{
if (isSpeedBoosting == true)
{
Move(speedModifier);
}
else
{
Move(1f);
}
if (syncTimer <= 0f) {
syncTimer = networkRefreshRate;
SyncTransform ();
} else {
syncTimer -= Time.deltaTime;
}
}
else
{
NetworkMove();
}
}
/// <summary>
/// This function is constantly called to upload the local player's position to the server so the server is
/// aware of this player's movement and can share this local players current position with other players in the game.
/// </summary>
public void SyncTransform() {
if (isLocalPlayer == true && client != null && client.IsConnected()) {
client.SendPlayerTransform(SharedData.storage["userId"], transform.position, transform.rotation, currentLife);
}
}
Here is a sample of the UDP sender class in my game client:
public void SendPlayerTransform(string playerId, Vector3 position, Quaternion rotation, int currentLife) {
Message.Writer writer = new Message.Writer(Message.MessageType.PlayerTransform, udpClient, remoteEndPoint);
// Write the timestamp of this message
writer.WriteLong(DateTime.UtcNow.Ticks);
// write the player id
writer.WriteString(SharedData.storage["userId"]);
// write the position vector
writer.WriteFloatArray(CommonGameFunctions.ConvertVectorToFloatArray(position));
// write the rotation vector
writer.WriteFloatArray(CommonGameFunctions.ConvertQuaternionToFloatArray(rotation));
writer.WriteInt (currentLife);
// Now send the message
writer.Send();
}
Here is a sample of where I receive the UDP messages on the game client:
public int HandleUdpMessages() {
if (udpTimerStarted == false) {
lastUdpMessageReceivedTime = DateTime.Now;
udpTimerStarted = true;
} else if (udpTimerStarted == true && udpClient.Available == 0){
TimeSpan t = DateTime.Now - lastUdpMessageReceivedTime;
if (t.Seconds >= 10f) {
// no message received for last 10 seconds then throw IO exception
//throw new SocketException();
}
}
if (udpClient.Available > 0) {
var messageReader = new Message.Reader (udpClient);
messageReader.BlockingRead (ref localEndPoint, UdpReceiveTimeout);
var messageType = messageReader.ReadMessageTypeUdp ();
lastUdpMessageReceivedTime = DateTime.Now;
Debug.Log ("Received udp message: " + messageType);
switch (messageType) {
// Player position update message
case Message.MessageType.PlayerTransform:
HandlePlayerTransform (messageReader);
break;
case Message.MessageType.PlayerScore:
HandlePlayerScore (messageReader);
break;
case Message.MessageType.RockHealth:
HandleRockHealth (messageReader);
break;
case Message.MessageType.PlayerHealth:
HandlePlayerHealth (messageReader);
break;
case Message.MessageType.ShieldHealth:
HandleShieldHealth (messageReader);
break;
default:
Debug.LogError ("Unhandled message " + messageType);
break;
}
}
return 0;
}
public void HandlePlayerTransform(Message.Reader reader)
{
long timeStamp = reader.ReadLong ();
string playerId = reader.ReadString();
if (playerMessageTimeStamps [playerId].latestPlayerTransform > timeStamp)
return;
Vector3 position = new Vector3();
Quaternion rotation = new Quaternion();
// read position
position = CommonGameFunctions.ConvertFloatArrayToVector3(reader.ReadFloatArray(3));
rotation = CommonGameFunctions.ConvertFloatArrayToQuaternion(reader.ReadFloatArray(4));
// Now update the transform of the right player
Player player = Player.playerTable[playerId];
if (player == null) {
return;
}
player.SetNetworkPostion(position);
player.SetNetworkRotation(rotation);
}
On my server this is the main game loop which runs on its own dedicated thread.
// Now all the players are connected to the server
// We can start the main game loop
while (gameRunning == true) {
HandlePlayersWhoDroppedOut ();
if (PlayersLeftGame () == true) {
DisconnectAllPlayers ();
Debug.LogError ("Player's left match, returning from thread");
return;
} else {
foreach (NetworkPlayer p in participants) {
try {
p.HandleTcpMessages ();
p.HandleUdpMessages ();
} catch (IOException e) {
droppedPlayers.Add (p);
}
}
try {
RespawnRocksIfDestroyed ();
} catch (System.IO.IOException e) {
DisconnectAllPlayers ();
return;
Debug.LogError ("Failed to spawn rocks");
}
}
}

The problem with my code was that I was reading exactly one UDP message in each iteration of the UDP message handler function. I changed my function to read ALL the available UDP messages in the buffer and the lag reduced by 80%. UDP messages queue up in the buffer quicker than the message handler function repeats so this is why the problem was happening.

Related

How to enable notifications BLE, NINA B1

I wrote an Android Phone app in Android Studio that connects to a UbloX NINA B1 to send and receive data on the SPS Service.
I'm having issues with the incoming data from the NINA B1 (Peripheral). I'm not sure if I connected correctly and turned the notifications on correctly.
Below is the code where I do the connection to the SPS Service. (Hardcoded to select Group 3 and child 0)
#RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN_MR2)
// Clicked on a Caracteristic (eg. FIFO or Credits)
public boolean enableNotification() {
// Hardcode for SPS service on NINA B112, can only use this service, other services will not be used
// This groupPosition and childPosition was determined from A_05 code, The selectable list gave these values when selecting SPS service
int groupPosition = 3;
int childPosition = 0;
BluetoothGattCharacteristic characteristic;
characteristic = characteristics_HashMapList.get(services_ArrayList.get(groupPosition).getUuid().toString()).get(childPosition);
// Todo find a better way to do below two lines. This is a temp way to pass characteristic & mBTLE_Service to static variables to use in HomeFragment for sending data
//Copy characteristics of SPS service to static act_characteristic for use by HomeFragment
this.act_characteristic = characteristic;
//Copy mBTLE_Service of SPS service to static act_service for use by HomeFragment
this.act_service = mBTLE_Service;
if (Utils.hasWriteProperty(characteristic.getProperties()) != 0) {
String uuid = characteristic.getUuid().toString();
//act_characteristic.setTitle(uuid);
//act_characteristic.setService(mBTLE_Service);
//act_characteristic.setCharacteristic(characteristic);
//dialog_btle_characteristic.show(getFragmentManager(), "Dialog_BTLE_Characteristic");
} if (Utils.hasReadProperty(characteristic.getProperties()) != 0) {
if (mBTLE_Service != null) {
mBTLE_Service.readCharacteristic(characteristic);
}
} if (Utils.hasNotifyProperty(characteristic.getProperties()) != 0) {
if (mBTLE_Service != null) {
mBTLE_Service.setCharacteristicNotification(characteristic, true);
}
}
return false;
}
Here is where I set the notifications ON, this part I'm not so confident about.
#RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN_MR2)
public void setCharacteristicNotification(BluetoothGattCharacteristic characteristic, boolean enabled) {
if (mBluetoothAdapter == null || mBluetoothGatt == null) {
Log.w(TAG, "BluetoothAdapter not initialized");
return;
}
mBluetoothGatt.setCharacteristicNotification(characteristic, enabled);
BluetoothGattDescriptor descriptor = characteristic.getDescriptor(UUID.fromString(getString(R.string.CLIENT_CHARACTERISTIC_CONFIG)));
// Todo: if the indications and notifications is to be used, then mode the indications part back into setCharacteristicNotification() and add a check for Indications, then change below code to set both indication and notify
if (enabled) {
// Enable INDICATION & NOTIFICATION
final byte[] ENABLE_INDICATION_NOTIFICATION = {0x03, 0x00};
descriptor.setValue(ENABLE_INDICATION_NOTIFICATION);
}
else {
descriptor.setValue(BluetoothGattDescriptor.DISABLE_NOTIFICATION_VALUE);
}
//ToDo Shorten the delay time so that the Notifications Enable still works
// Delay in milli seconds
int m_sec = 200;
Delay.delay(m_sec, new Delay.DelayCallback() {
#Override
public void afterDelay() {
// Enable Notifications after 200 m_sec Delay
mBluetoothGatt.writeDescriptor(descriptor);
}
});
}
This is where I handle the incoming Bytes, I send a Modbus message from the Phone to NINA B1, then NINA B1 replies with a Modbus message. The Incoming byte count is always < 20 bytes. And I fill the RxBuff until the correct amount of bytes are received AND the Slave Address is correct, then I decode the received message.
#RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN_MR2)
private void broadcastUpdate(final String action, final BluetoothGattCharacteristic characteristic) {
final Intent intent = new Intent(action);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR2) {
intent.putExtra(EXTRA_UUID, characteristic.getUuid().toString());
}
// For all other profiles, writes the data formatted in HEX.
// Only Pack 20 bytes at a time coming from BLE server into data[]
final byte[] rx_Data;
int tempSlavAdr;
rx_Data = characteristic.getValue();
if (rx_Data != null && rx_Data.length > 0) {
// Only handle message if request came from ReadInput_Thread
if (this.request_flag) {
// ToDO: See if other non Modbus data arrives between packets
// Populate RxBuff
for (int i = 0; i < rx_Data.length; i++) {
this.RxBuff[this.WrPtr++] = rx_Data[i];
}
Log.d(TAG,"QTY Bytes in rx_Data = " + (Integer)rx_Data.length);
// Start Decode message only after all expected bytes are received && first message is Slave Address
// Prevent Negative numbers in Slave Address: tempSlavAdr is used in the the next if statement
tempSlavAdr = (byte) this.RxBuff[0];
if (tempSlavAdr < 0) tempSlavAdr += 256;
if ((this.WrPtr == FragmentHome.ExpectedCount_sent) && (tempSlavAdr == slaveAddr)) {
// Copy RxBuff over to Dec_RxBuff
int Dec_RxBuff[] = new int[255];
for (int i = 0; i < this.WrPtr; i++) {
Dec_RxBuff[i] = (this.RxBuff[i]);
Dec_RxBuff[i] += 256;
Dec_RxBuff[i] = Dec_RxBuff[i] & 0xFF;
}
// Clear flag indicating that Thread Send a Request
this.request_flag = false;
message_rx = false;
// Decode ModbusMessage and message Good
if (modbusHandler.DecodeModbusMessage(Dec_RxBuff)){
message_rx = true;
}
// Decode ModbusMessage and message Bad
else{
message_rx = false;
}
// Clear buffers
WrPtr = 0;
Arrays.fill(rx_Data, (byte) 0);
Arrays.fill(RxBuff, (byte) 0);
// Todo What if WrPtr stop short of Expected counter? Do some protection
// WrPtr > ExpectedCount Clear Buffers
} else if (WrPtr > FragmentHome.ExpectedCount_sent) {
// Clear buffers
// HomeFragment.set_Actual(false);
Log.d(TAG,"RX Count to big expected " + FragmentHome.ExpectedCount_sent + " got " + WrPtr);
WrPtr = 0;
Arrays.fill(rx_Data, (byte) 0);
Arrays.fill(RxBuff, (byte) 0);
}
// Todo Use this intent to pass data to a service to Decode Modbus Data (Service not written yet)
// intent.putExtra(EXTRA_DATA, new String(data) + "\n" + Utils.hexToString(data));
}
}
else {
//intent.putExtra(EXTRA_DATA, "0");
}
//sendBroadcast(intent);
}
I still get some data loss, and not sure how to handle this. Phone and NINA B1 is next to one another so distance is not a problem.
Can I get some help on how to set the indications correctly? And why I might lose bytes.
Marinus

Eliminating volume envelope retrigger clicks - Jsyn on Android

I am looking for ideas on how to handle envelope re-triggering of new notes in a monophonic sampler setup causing clicks if the previous note's envelope hasn't finished. In the current setup the previous note's instance is killed on the spot when a new note is triggered (the synth.stop method call), causing a click as the envelope doesn't get a chance to finish and reach 0 volume. Any hints are welcome.
I have also added in the below code my own un-satisfactory solution putting the gain of the voice to 0 and then putting the voice to sleep for 70ms. This introduces a 70ms latency to the user interaction but gets rid of any clicks. Any values below 70ms in the sleep don't solve the clicking.
The variable are public static at the moment just so I can still play around with where I'm calling them.
Here is my listener code:
buttonNoteC1Get.setOnTouchListener(new View.OnTouchListener() {
#Override
public boolean onTouch(View v, MotionEvent event) {
if (event.getAction() == MotionEvent.ACTION_UP) {
buttonNoteC1Get.setBackgroundColor(myColorWhite); // reset gui color
if (sample.getSustainBegin() > 0) { // trigger release for looping sample
ampEnv.dataQueue.queue(ampEnvelope, 3, 1); // release called
}
limit = 0; // reset action down limiter
return true;
}
if (limit == 0) { // respond only to first touch event
if (samplePlayer != null) { // check if a previous note exists
synth.stop(); // stop instance of previous note
}
buttonNoteC1Get.setBackgroundColor(myColorGrey); // key pressed gui color
samplePitch = octave * 1; // set samplerate multiplier
Sampler.player(); // call setup code for new note
Sampler.play(); // play new note
limit = 1; // prevent stacking of action down touch events
}
return false;
}
}); // end listener
Here is my Sampler code
public class Sampler {
public static VariableRateDataReader samplePlayer;
public static LineOut lineOut;
public static FloatSample sample;
public static SegmentedEnvelope ampEnvelope;
public static VariableRateMonoReader ampEnv;
public static MixerMonoRamped mixerMono;
public static double[] ampData;
public static FilterStateVariable mMainFilter;
public static Synthesizer synth = JSyn.createSynthesizer(new JSynAndroidAudioDevice());
// load the chosen sample, called by instrument select spinner
static void loadSample(){
SampleLoader.setJavaSoundPreferred(false);
try {
sample = SampleLoader.loadFloatSample(sampleFile);
} catch (IOException e) {
e.printStackTrace();
}
} // end load sample
// initialize sampler voice
static void player() {
// Create an amplitude envelope and fill it with data.
ampData = new double[] {
envA, 0.9, // pair 0, "attack"
envD, envS, // pair 2, "decay"
0, envS, // pair 3, "sustain"
envR, 0.0, // pair 4, "release"
/* 0.04, 0.0 // pair 5, "silence"*/
};
// initialize voice
ampEnvelope = new SegmentedEnvelope(ampData);
synth.add(ampEnv = new VariableRateMonoReader());
synth.add(lineOut = new LineOut());
synth.add(mixerMono = new MixerMonoRamped(2));
synth.add(mMainFilter = new FilterStateVariable());
// connect signal flow
mixerMono.output.connect(mMainFilter.input);
mMainFilter.output.connect(0, lineOut.input, 0);
mMainFilter.output.connect(0, lineOut.input, 1);
// set control values
mixerMono.amplitude.set(sliderVal / 100.0f);
mMainFilter.amplitude.set(0.9);
mMainFilter.frequency.set(mainFilterCutFloat);
mMainFilter.resonance.set(mainFilterResFloat);
// initialize and connect sampler voice
if (sample.getChannelsPerFrame() == 1) {
synth.add(samplePlayer = new VariableRateMonoReader());
ampEnv.output.connect(samplePlayer.amplitude);
samplePlayer.output.connect(0, mixerMono.input, 0);
samplePlayer.output.connect(0, mixerMono.input, 1);
} else if (sample.getChannelsPerFrame() == 2) {
synth.add(samplePlayer = new VariableRateStereoReader());
ampEnv.output.connect(samplePlayer.amplitude);
samplePlayer.output.connect(0, mixerMono.input, 0);
samplePlayer.output.connect(1, mixerMono.input, 1);
} else {
throw new RuntimeException("Can only play mono or stereo samples.");
}
} // end player
// play the sample
public static void play() {
if (samplePlayer != null)
{samplePlayer.dataQueue.clear();
samplePlayer.rate.set(sample.getFrameRate() * samplePitch); // set pitch
}
// start the synth engine
synth.start();
lineOut.start();
ampEnv.start();
// play one shot sample
if (sample.getSustainBegin() < 0) {
samplePlayer.dataQueue.queue(sample);
ampEnv.dataQueue.queue( ampEnvelope );
// play sustaining sample
} else {
samplePlayer.dataQueue.queueOn(sample);
ampEnv.dataQueue.queue( ampEnvelope, 0,3);
ampEnv.dataQueue.queueLoop( ampEnvelope, 1, 2 );
}
} }
Unsatisfactory solution that introduces 70ms of latency, changing the action down listener handling of a previous note to this:
if (limit == 0) {
if (samplePlayer != null) {
mixerMono.amplitude.set(0);
try {
synth.sleepFor(0.07);
synth.stop(); // stop instance of previous note
}catch (InterruptedException e) {
e.printStackTrace();
}
}
You should not call synth.start() and synth.stop() for every note. Think of it like powering on a physical synthesizer. Just start the synth and the lineOut once. If the ampEnv is connected indirectly to something else that is start()ed then you do not need to start() the ampEnv.
Then just queue your samples and envelopes when you want to start a note.
When you are all done playing notes then call synth.stop().

Client's objects movement not syncing across the Network

I'm making a 2-player android game using UNET. Now, all the movements of the host's objects are syncing across the network therefore it's working fine. But when the object on the client's side moves, it moves but it doesn't move in the host's screen. Therefore, the movement is not syncing.
I already attached NetworkIdentity, NetworkTransform, and PlayerController script to it. As well as the box collider (for the raycast).
The server and the client has the same script in the PlayerController but the only difference is, host could only move objects with Player tags and objects with Tagger tags for the client.
void Update () {
if(!isLocalPlayer){
return;
}
if(isServer){
Debug.Log("Server here.");
if (Input.GetMouseButtonDown(0))
{
Vector2 cubeRay = Camera.main.ScreenToWorldPoint(Input.mousePosition);
RaycastHit2D cubeHit = Physics2D.Raycast(cubeRay, Vector2.zero);
if (cubeHit)
{
if(cubeHit.transform.tag=="Player")
{
if (this.target != null)
{
SelectMove sm = this.target.GetComponent<SelectMove>();
if (sm != null) { sm.enabled = false; }
}
target = cubeHit.transform.gameObject;
selectedPlayer();
}
}
}
}
if(!isServer){
Debug.Log("Client here.");
if (Input.GetMouseButtonDown(0))
{
Vector2 cubeRay = Camera.main.ScreenToWorldPoint(Input.mousePosition);
RaycastHit2D cubeHit = Physics2D.Raycast(cubeRay, Vector2.zero);
if (cubeHit)
{
if(cubeHit.transform.tag=="Tagger")
{
if (this.target != null)
{
SelectMove sm = this.target.GetComponent<SelectMove>();
if (sm != null) { sm.enabled = false; }
}
target = cubeHit.transform.gameObject;
selectedPlayer();
}
}
}
}
}
I'm using (!isServer) to identify client because isClient sometimes doesn't work fine on my project. I also tried using it again to test it out, but still no luck.
You dont need to use tags to move players this one script PlayerController is enough using only isLocalPlayer check and try disabling this script using !isLocalPlayer on both clients. Use this for reference http://docs.unity3d.com/Manual/UNetSetup.html and check thier sample tutorial

Android native webrtc: add video after already connected

I have successfully been running WebRTC in my Android app for a while, using libjingle.so and PeerConnectionClient.java, etc., from Google's code library. However, I am now running into a problem where a user starts a connection as audio only (i.e., an audio call), but then toggles video on. I augmented the existing setVideoEnabled() in PeerConnectionClient as such:
public void setVideoEnabled(final boolean enable) {
executor.execute(new Runnable() {
#Override
public void run() {
renderVideo = enable;
if (localVideoTrack != null) {
localVideoTrack.setEnabled(renderVideo);
} else {
if (renderVideo) {
//AC: create a video track
String cameraDeviceName = VideoCapturerAndroid.getDeviceName(0);
String frontCameraDeviceName =
VideoCapturerAndroid.getNameOfFrontFacingDevice();
if (numberOfCameras > 1 && frontCameraDeviceName != null) {
cameraDeviceName = frontCameraDeviceName;
}
Log.i(TAG, "Opening camera: " + cameraDeviceName);
videoCapturer = VideoCapturerAndroid.create(cameraDeviceName);
if (createVideoTrack(videoCapturer) != null) {
mediaStream.addTrack(localVideoTrack);
localVideoTrack.setEnabled(renderVideo);
peerConnection.addStream(mediaStream);
} else {
Log.d(TAG, "Local video track is still null");
}
} else {
Log.d(TAG, "Local video track is null");
}
}
if (remoteVideoTrack != null) {
remoteVideoTrack.setEnabled(renderVideo);
} else {
Log.d(TAG,"Remote video track is null");
}
}
});
}
This allows me successfully see a local inset of the device's video camera, but it doesn't send the video to the remove client. I thought the peerConnection.addStream() call would do that, but perhaps I am missing something else?
To avoid building an external mechanism of communication between peers that will involve an answer from the second peer that the new stream can be added, you can always start with existing (but sometimes empty) video stream. Now it is just the matter of filling this stream with content when (and if) necessary.

Problems when sending a continuous stream of data over BLE

I'm wondering if anybody can help me figure out what is causing the data I am sending to become corrupt.
My setup is currently an Arduino pro mini with a HM-10 bluetooth module connected (I have also tried HM-11 Module too) and an Android application to receive the bluetooth data.
Module setup: http://letsmakerobots.com/node/38009
If I send data with big enough intervals then the data is fine, but if I send the data continuously I see messages getting mixed up and lost. To test this I send "$0.1,0.2,0.3,0.4,0.5" to the Android application from the Arduino, sometimes the stream of data appears to send fine but other times it is really quite scrambled. Please see the below graphs that demonstrate this:
Good case:
Bad case:
Arduino code:
String inputString = ""; //Hold the incoming data.
boolean stringComplete = false; //Determines if the string is complete.
boolean realtime = false;
void setup()
{
Serial.begin(9600);
delay(500);
Serial.print("AT+START");
delay(500);
}
void loop()
{
if(stringComplete)
{
if(inputString.equals("rStart"))
{
Serial.println("$startACK");
realtime = true;
}
else if(inputString.equals("stop"))
{
Serial.println("$stopACK");
realtime = false;
}
else{
Serial.print(inputString);
}
inputString = "";
stringComplete = false;
}
if(realtime)
{
Serial.println("$0.1,0.2,0.3,0.4,0.5,0.6");
delay(10);
}
}
void serialEvent() {
while (Serial.available())
{
// get the new byte:
char inChar = (char)Serial.read();
if (inChar == '\n')
{
stringComplete = true;
}
else
{
inputString += inChar;
}
}
}
The Android side just receives the data and then parses it in an IntentService:
#Override
protected void onHandleIntent(Intent intent) {
//Incoming command.
String rawData = intent.getStringExtra(DataProcessingIntentService.REQUEST);
//Append our new data to our data helper.
Log.i(this.getClass().getName(), "Previous Raw: (" + DataProcessingHelper.getInstance().getData() + ")");
DataProcessingHelper.getInstance().appendData(rawData);
Log.i(this.getClass().getName(), "New Raw: (" + DataProcessingHelper.getInstance().getData() + ")");
commandStartIndex = DataProcessingHelper.getInstance().getData().indexOf("$");
commandEndIndex = DataProcessingHelper.getInstance().getData().indexOf("\n");
//Set this as the data starting point.
if(commandStartIndex != -1){
DataProcessingHelper.getInstance().offsetData(commandStartIndex);
}
//Ensure that a command has been found and that the end index is after the starting index.
if(commandStartIndex != -1 && commandEndIndex > commandStartIndex){
//Remove the command structure from the command.
command = DataProcessingHelper.getInstance().getData().substring(commandStartIndex+1, commandEndIndex-1); //Remove the \r\n end command.
DataProcessingHelper.getInstance().offsetData(commandEndIndex+1);
if(command.length() > 1){
//Split the data out of the comand.
splitData = command.split(",");
Log.i(this.getClass().getName(), "Broadcasting the processed data. (" + command + ")");
//Broadcast data.
Intent broadcastIntent = new Intent();
broadcastIntent.setAction(DataProcessingIntentService.RESPONSE);
broadcastIntent.addCategory(Intent.CATEGORY_DEFAULT);
broadcastIntent.putExtra(DataProcessingIntentService.RESPONSE, splitData);
sendBroadcast(broadcastIntent);
}else{
Log.e(this.getClass().getName(), "Command is less than 1 character long!");
}
}
}
Thank you for any help!
I have now figured out what was causing this problem. It appears that BLE only supports a maximum of 20 bytes per a transaction. The time between these transactions is different depending on what you are using. I'm currently using notifications which means that I can send 20 bytes every 7.5 milliseconds maximum. I have opted for 10 milliseconds to be safe. I will now need to look into breaking up packets into 20 bytes maximum to ensure no data corruption.

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