นี่เป็นตัวอย่างจาก https://www.ccsinfo.com ครับ#USE RS232 (BAUD = 9600, XMIT = PIN_B0, RCV = PIN_B1, STREAM = COM_A)
#USE RS232 (BAUD = 9600, XMIT = PIN_B2, RCV = PIN_B3, STREAM = COM_B)
void main(void) {
char c;
fprintf(COM_A, "Online\n\r");
fprintf(COM_B, "Online\n\r");
while(TRUE) {
c = fgetc(COM_A);
fputc(c, COM_A);
fputc(c, COM_B);
}
}