[PIC] PIC32 RS485 using MAX14783E

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#define UART_BAUDRATE 9600
#define PBCLK 100000000  // Adjust according to your peripheral clock frequency
#define BUFFER_SIZE 200
#define DE_PIN LATJbits.LATJ2  // Driver Enable (DE)
#define RE_PIN LATJbits.LATJ3  // Receiver Enable (RE)
 
char txBuffer[BUFFER_SIZE];
char rxBuffer[BUFFER_SIZE];
volatile int rxIndex = 0;
volatile bool messageReceived = false;
 
void UART6_Init() {
    // UART6 Pin Configuration
    U6RXRbits.U6RXR = 0b0110;  // Map U6RX to RD5
    RPD4Rbits.RPD4R = 0b0100;  // Map U6TX to RD4
 
    // UART6 Configuration
    U6MODE = 0;  // Reset UART
    U6BRG = ((PBCLK / (16 * UART_BAUDRATE)) - 1)/2;  // Set baud rate
    U6STA = 0;  // Clear status
    U6STAbits.UTXEN = 1;  // Enable TX
    U6STAbits.URXEN = 1;  // Enable RX
    U6MODEbits.ON = 1;    // Enable UART6
 
    // Enable UART RX Interrupt
    IPC47bits.U6RXIP = 6;  // Set priority
    IPC47bits.U6RXIS = 1;  // Set subpriority
    IEC5bits.U6RXIE = 1;   // Enable RX interrupt
}
 
void __ISR(_UART6_RX_VECTOR, IPL6SOFT) UART6_RX_ISR(void) {
    char received = U6RXREG;  // Read received byte
    MZ_LED1 = !MZ_LED1;
    rxBuffer[rxIndex++] = received;
    if (received == '\n') {  // End of message
        messageReceived = true;
        rxBuffer[rxIndex] = '\0';  // Null-terminate the string
        rxIndex = 0;
    }
    IFS5CLR = _IFS5_U6RXIF_MASK;  // Clear RX interrupt flag
}
 
void sendMessage(const char* message) {
    DE_PIN = 1;  // Enable transmitter
    RE_PIN = 1;  // Disable receiver
    delay_ms(1);  // Allow DE/RE signal to settle
    for (int i = 0; i < strlen(message); i++) {
        while (U6STAbits.UTXBF);  // Wait for TX buffer to be empty
        U6TXREG = message[I];
    }
    while (!U6STAbits.TRMT);  // Wait for transmission to complete
    delay_ms(1);  // Allow bus to stabilize
    DE_PIN = 0;  // Disable transmitter
    RE_PIN = 0;  // Enable receiver
}
 
void main()
{
   
    TRISJbits.TRISJ2 = 0;  // Set J2 as output (DE)
    TRISJbits.TRISJ3 = 0;  // Set J3 as output (RE)
    DE_PIN = 0;  // Start in receive mode
    RE_PIN = 0;  // Start in receive mode
    UART6_Init();
 
    while(1){
//testing 485 communication
        //master
        sendMessage("0x01\n");
        delay_ms(1000);  // Adjust delay as needed
        if (messageReceived) {
         messageReceived = false;
         debug_print("message received/n");
        }
               
        //slave
        if (messageReceived) {
            messageReceived = false;
            // Echo the received message back to the master
            debug_print("received\n");
            sendMessage("Message Received: ");
            sendMessage(rxBuffer);
        }
       
    }
}