I would guess Travis's example works well, but I'm going to offer a different spin on the topic. You can define XMC_DEBUG_ENABLE as TRUE. this ties the printf() new lib commands to your application (xmc_common.h). So now, newlib functions _write and _read are usable. You can configure a UART app to tie to the these commands. Just bring in a UART app and configure to pins P1.3 (XMC Rx) and P1.2 (XMC Tx). So your code looks like the following:
#include
#define XMC_DEBUG_ENABLE TRUE
/* This adds the stdio "putchar/printf" functions to transmit */
int _write(int file, uint8_t *buf, int nbytes)
{
if(UART_Transmit(&UART_0, buf, nbytes) == UART_STATUS_SUCCESS) {
while(UART_0.runtime->tx_busy) {
}
}
return nbytes;
}
/* This adds the stdio "getchar" functions to receive from UART_0 */
int _read(int file, uint8_t *buf, int nbytes)
{
if(UART_Receive(&UART_0, buf, nbytes) != UART_STATUS_SUCCESS) {
while(UART_0.runtime->rx_busy)
{
}
}
return nbytes;
}
Note that the code above waits for the UART buffer to run empty (runtime->tx_busy is a command that could add long latency), so you could drive this as interrrupt based feedback or no feedback at all. With the addition of the UART configuration, just add the app and configure baud rate and pins, you now have printf. Make sure your PC terminal aligns to the baud rate of the UART app settings.
