LAUNCHXL-F28379D: Receive data from the LAUNCHXL using SCI protocol

Part Number: LAUNCHXL-F28379D
Other Parts Discussed in Thread: C2000WARE

Hello,

I'm trying to use the SCI protocol on my LAUNCHXL-F28379D. As usual, I readed the documentation and tried the examples, but they didn't work. I switch from the SCIA to SCIB (because the LAUNCHXL doesn't have PINs on SCIA) and it still doesn't work. I simplified the code, keeping the essential, so this is my code :

#include "F28x_Project.h"

#define TX 18


void scib_echoback_init(void);
void scib_fifo_init(void);
void scib_xmit(int a);
void scib_msg(char *msg);


void main(void)
{
    char *msg;

   InitSysCtrl();

   // GPIO
   InitGpio();
   GPIO_SetupPinMux(TX, GPIO_MUX_CPU1, 1);
   GPIO_SetupPinOptions(TX, GPIO_OUTPUT, GPIO_ASYNC);

   // Interrupts
   DINT;
   InitPieCtrl();
   IER = 0x0000;
   IFR = 0x0000;
   InitPieVectTable();
   EINT;

   // SCI
   scib_fifo_init();
   scib_echoback_init();

   for (;;) {
       msg = "a\0";
       scib_msg(msg);
   }
}

void scib_echoback_init()
{
    ScibRegs.SCICCR.all = 0x0007;   // 1 stop bit,  No loopback
                                    // No parity,8 char bits,
                                    // async mode, idle-line protocol
    ScibRegs.SCICTL1.all = 0x0003;  // enable TX, RX, internal SCICLK,
                                    // Disable RX ERR, SLEEP, TXWAKE
    ScibRegs.SCICTL2.all = 0x0003;
    ScibRegs.SCICTL2.bit.TXINTENA = 1;
    ScibRegs.SCICTL2.bit.RXBKINTENA = 1;

    //
    // SCIB at 9600 baud
    // @LSPCLK = 50 MHz (200 MHz SYSCLK) HBAUD = 0x02 and LBAUD = 0x8B.
    // @LSPCLK = 30 MHz (120 MHz SYSCLK) HBAUD = 0x01 and LBAUD = 0x86.
    //
    ScibRegs.SCIHBAUD.all = 0x0002;
    ScibRegs.SCILBAUD.all = 0x008B;

    ScibRegs.SCICTL1.all = 0x0023;  // Relinquish SCI from Reset
}

void scib_xmit(int a)
{
    while (ScibRegs.SCIFFTX.bit.TXFFST != 0) {}
    ScibRegs.SCITXBUF.all =a;
}

void scib_msg(char * msg)
{
    int i;
    i = 0;
    while(msg[i] != '\0')
    {
        scib_xmit(msg[i]);
        i++;
    }
}

void scib_fifo_init()
{
    ScibRegs.SCIFFTX.all = 0xE040;
    ScibRegs.SCIFFRX.all = 0x2044;
    ScibRegs.SCIFFCT.all = 0x0;
}

As you can see, I'm just sending over and over the 'a' character. In debug mode, I checked SCITXBUF from the ScibRegs and it is filled correctly (0x0061). So I think the configuration of the SCI is right. For reading, I'm using an Arduino UNO with the following code :

void setup() {
  Serial.begin(9600);
}

void loop() {
  if (Serial.available() > 0) {
    int msg = Serial.read();
    Serial.println(msg);
  }
}

Both cards are connected to my computer via USB. I connected the PIN 4 (GPIO18) of the TI card to the PIN 0 (RX) of the Arduino. But the arduino RX led doesn't light up and the Serial monitor stay empty.

I absolutly don't know where the problem is. I will be able to check on a scope monday if needed.

Thanks for your help !