feat: ESP MTU 512 + dynamic Android chunk size based on negotiated MTU

This commit is contained in:
eddy 2026-07-30 19:15:55 +02:00
commit fcbf1e9b5f
3 changed files with 14 additions and 6 deletions

View file

@ -59,6 +59,7 @@ class BleRelayManager(
private var otaCharacteristic: BluetoothGattCharacteristic? = null
private var espVersion: String? = null
private var appVersion: String = ""
private var negotiatedMtu: Int = 23
interface OtaNotifyCallback {
fun onOtaNotify(status: Int, seq: Int)
@ -229,6 +230,8 @@ class BleRelayManager(
fun getEspVersion(): String? = espVersion
fun getNegotiatedMtu(): Int = negotiatedMtu
@SuppressLint("MissingPermission")
private fun connectToDevice(device: android.bluetooth.BluetoothDevice) {
handler.post { callbacks.onStatusChanged(BleStatus.Connecting) }
@ -274,6 +277,7 @@ class BleRelayManager(
@SuppressLint("MissingPermission")
override fun onMtuChanged(gatt: android.bluetooth.BluetoothGatt, mtu: Int, status: Int) {
Log.d(TAG, "MTU changed to $mtu")
negotiatedMtu = mtu
val service = gatt.getService(SERVICE_UUID)
if (service != null) {
relayCharacteristic = service.getCharacteristic(CHARACTERISTIC_UUID)

View file

@ -18,15 +18,12 @@ class OtaManager(
) {
companion object {
private const val TAG = "OtaManager"
private const val OTA_CHUNK_DATA_SIZE = 248
private const val OTA_CMD_START: Byte = 0x10
private const val OTA_STATUS_ACK: Byte = 0x00
private const val OTA_STATUS_COMPLETE: Byte = 0x10
private const val OTA_STATUS_ERROR: Byte = 0x11
private const val OTA_START_TIMEOUT_MS = 10000L
private const val OTA_CHUNK_TIMEOUT_MS = 2000L
private const val OTA_FINAL_TIMEOUT_MS = 10000L
private const val MAX_RETRIES = 3
private const val OTA_ESP_MAX_CHUNK = 500
}
interface OtaCallback {
@ -36,10 +33,16 @@ class OtaManager(
}
private var firmwareData: ByteArray? = null
private var chunkDataSize: Int = 248
private fun calculateChunkSize(mtu: Int): Int {
return minOf(maxOf(mtu - 3 - 4, 20), OTA_ESP_MAX_CHUNK)
}
fun loadFirmware(): Boolean {
return try {
firmwareData = context.assets.open("firmware/firmware.bin").readBytes()
chunkDataSize = calculateChunkSize(relayManager.getNegotiatedMtu())
true
} catch (e: Exception) {
Log.e(TAG, "Failed to load firmware", e)
@ -85,13 +88,13 @@ class OtaManager(
}
} catch (_: kotlinx.coroutines.TimeoutCancellationException) {}
val totalChunks = (fw.size + OTA_CHUNK_DATA_SIZE - 1) / OTA_CHUNK_DATA_SIZE
val totalChunks = (fw.size + chunkDataSize - 1) / chunkDataSize
var seq = 0
var offset = 0
while (offset < fw.size) {
val remaining = fw.size - offset
val chunkSize = minOf(remaining, OTA_CHUNK_DATA_SIZE)
val chunkSize = minOf(remaining, chunkDataSize)
val packet = ByteBuffer.allocate(4 + chunkSize).order(ByteOrder.BIG_ENDIAN)
packet.putInt(seq)

View file

@ -338,6 +338,7 @@ void setup() {
}
Serial.println("LED blink done, starting BLE...");
NimBLEDevice::setMTU(512);
NimBLEDevice::init("SylDa_Server");
NimBLEServer *pServer = NimBLEDevice::createServer();