LAUNCHXL-F28379D: SCI works only on the SCIA pin

Part Number: LAUNCHXL-F28379D

Hello,

I'm trying to communicate using the SCI protocol using the LAUNCHXL-F28379D. As usual, I have read the TRM and tried the example code. The example code worked perfectly, because it uses SCIA. When I switch to use SCIB or any other one (C or D) it just doesn't work and I can't find why, even with the GPIO Mux correctly set up. This is my code, trying to talk over SCIBTX :

#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();

    EALLOW;
    // Set the mux to SCITXDB on GPIO 18
    GpioCtrlRegs.GPAGMUX2.bit.GPIO18 = 0;
    GpioCtrlRegs.GPAMUX2.bit.GPIO18 = 2;
    // Select CPU 1
    GpioCtrlRegs.GPACSEL3.bit.GPIO18 = 0;
    // Set GPIO 18 as output
    GpioCtrlRegs.GPADIR.bit.GPIO18 = 1;
    // Async mode
    GpioCtrlRegs.GPAQSEL2.bit.GPIO18 = 3;
    EDIS;

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

    // SCI
    scib_fifo_init();
    scib_echoback_init();

    for (;;) {
        msg = "Salut\n\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;  // Enable RXBKINTENA and TXINTENA

    //
    // 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;
}

I'm using the flag _LAUNCHXL_F28379D for the compiler.

Thanks for your help!