Test out some things

app/fskmodem.c

@@ -98,6 +98,88 @@ void MSG_ConfigureFSK(bool rx) {
 }
 
 
+uint16_t calculateCRC(uint8_t *data, size_t length) {
+    uint16_t crc = 0xFFFF; // Example CRC-16 initialization
+    for (size_t i = 0; i < length; i++) {
+        crc ^= data[i];
+        for (uint8_t j = 0; j < 8; j++) {
+            if (crc & 1) {
+                crc = (crc >> 1) ^ 0xA001; // Example polynomial (CRC-16-IBM)
+            } else {
+                crc >>= 1;
+            }
+        }
+    }
+    return crc;
+}
+
+
+void processReceivedPacket(DataPacket *packet) {
+    char String[31 + DataPacketDataSize];
+    char numBuf[11];  // Enough for any 64-bit unsigned integer
+    const unsigned int vfo = (gEeprom.CROSS_BAND_RX_TX == CROSS_BAND_OFF) ? gEeprom.RX_VFO
+                                                                          : gEeprom.TX_VFO;
+    if (dataPacket.dest == gEeprom.FSKSRCAddress) {
+        BK4819_PlaySingleTone(1000, 250, 127, true);
+        strcpy(String, "SMS by ");
+        itoa(packet->src, numBuf);  // Convert number to string
+        strcat(String, numBuf);
+        strcat(String, ": ");
+        strcat(String, (char *)packet->data);
+
+        UI_DisplayPopup(String);
+#ifdef ENABLE_FEAT_F4HWN
+        if (isMainOnly()) {
+                    UI_PrintStringSmallNormal(String, 2, 0, 5);
+                } else {
+                    UI_PrintStringSmallNormal(String, 2, 0, 3);
+                }
+#else
+        UI_PrintStringSmallNormal(String, 2, 0, 3);
+
+#endif
+
+    } else if (VfoState[vfo] == VFO_STATE_NORMAL && !TX_freq_check(gCurrentVfo->freq_config_TX.Frequency)) {
+        if (packet->ttl--) {
+            BK4819_ToggleGpioOut(BK4819_GPIO5_PIN1_RED, true);
+            MSG_FSKSendData(packet);
+            BK4819_ToggleGpioOut(BK4819_GPIO5_PIN1_RED, false);
+        }
+    }
+
+    memset(packet, 0, DataPacketDataSize); // Clear data after processing (example action)
+}
+
+
+bool MSG_FSKReceiveData() {
+    if (!(BK4819_ReadRegister(BK4819_REG_0C) & (1U << 1))) {
+        return false; // No data available
+    }
+
+    // Read the received data from FIFO
+    uint16_t *ptr = (uint16_t *) &inBoundPacket;
+    size_t wordCount = sizeof(inBoundPacket) / sizeof(uint16_t);
+
+    for (size_t i = 0; i < wordCount; i++) {
+        ptr[i] = BK4819_ReadRegister(BK4819_REG_5F);
+    }
+
+    // Clear the RX interrupt flag
+    BK4819_WriteRegister(BK4819_REG_02, 0);
+
+    // Validate checksum (assuming last 2 bytes are CRC-16)
+    size_t dataLength = sizeof(inBoundPacket.data) - 2;
+    uint16_t receivedCRC = (inBoundPacket.data[dataLength] << 8) | inBoundPacket.data[dataLength + 1];
+    uint16_t calculatedCRC = calculateCRC(inBoundPacket.data, dataLength);
+
+    if (receivedCRC == calculatedCRC) {
+        processReceivedPacket(&inBoundPacket);
+        return true;
+    }
+
+    return false; // CRC check failed
+}
+
 void MSG_EnableRX(const bool enable) {
 
     if (enable) {
@@ -111,8 +193,14 @@ void MSG_EnableRX(const bool enable) {
     }
 }
 
-void MSG_FSKSendData() {
+void MSG_FSKSendData(DataPacket *dataPacketIn) {
 
+    bool isAudioOn = gEnableSpeaker;
+    if (gEnableSpeaker) {
+        AUDIO_AudioPathOff();
+        BK4819_EnterTxMute();
+        gEnableSpeaker = false;
+    }
     // turn off CTCSS/CDCSS during FFSK
     const uint16_t css_val = BK4819_ReadRegister(BK4819_REG_51);
     BK4819_WriteRegister(BK4819_REG_51, 0);
@@ -163,8 +251,8 @@ void MSG_FSKSendData() {
     SYSTEM_DelayMs(100);
 
     {    // load the entire packet data into the TX FIFO buffer
-        uint16_t *ptr = (uint16_t *) &dataPacket;
-        size_t wordCount = sizeof(dataPacket) / sizeof(uint16_t);
+        uint16_t *ptr = (uint16_t *) dataPacketIn;
+        size_t wordCount = sizeof(*dataPacketIn) / sizeof(uint16_t);
 
         for (size_t i = 0; i < wordCount; i++) {
             BK4819_WriteRegister(BK4819_REG_5F, ptr[i]);
@@ -211,9 +299,16 @@ void MSG_FSKSendData() {
     gUpdateDisplay = true;
     gFlagEndTransmission = false;
 
+    if (isAudioOn) {
+        AUDIO_AudioPathOn();
+        gEnableSpeaker = true;
+        BK4819_ExitTxMute();
+    }
+
 }
 
 void prepareDataPacket() {
     dataPacket.src = gEeprom.FSKSRCAddress;
     dataPacket.seq = seq++;
+    dataPacket.ttl = 20;
 }