#include "mbed.h"

Serial pc(USBTX, USBRX); // tx, rx
Serial device(p9, p10);  // tx, rx

int main() {
device.baud(4800);
    while(1) {
    pc.printf("test print %d%d%d\r\n", 1, 2, 3);
    }
}

#include "mbed.h"

Serial pc(USBTX, USBRX); // tx, rx
//Serial device(p9, p10);  // tx, rx

int main() {
//device.baud(4800);
    while(1) {
    pc.printf("test print %d%d%d\r\n", 1, 2, 3);
    }
}

Curious problem arises when I added a second serial instance to my program. When adding the Second serial instance Serial device(p9, p10); The Serial pc stops sending data to the terminal screen listening on the mbeds serial port. Comment the Serial device(p9, p10) and the device.baud(4800); and compile message start to flow to the terminal screen. Is this a bug? BELOW NO MESSAGES in the terminal screen <<code>> #include "mbed.h" Serial pc(USBTX, USBRX); // tx, rx Serial device(p9, p10); // tx, rx int main() { device.baud(4800); while(1) { pc.printf("test print %d%d%d\r\n", 1, 2, 3); } } <</code>> BELOW Messages flow <<code>> #include "mbed.h" Serial pc(USBTX, USBRX); // tx, rx //Serial device(p9, p10); // tx, rx int main() { //device.baud(4800); while(1) { pc.printf("test print %d%d%d\r\n", 1, 2, 3); } } <</code>>

LPC11U24 has only one UART, and it's connected both to USB (via the interface chip) and p9/p10.

Thanks for the reply The representation of the LPC11U24 is a little mis leading. Lots of examples are given which are specific to the LPC1768 and fail to indicate those examples will not work with the LPC11U24. Very frustrating.

Agreed, I made the same remark in another thread. Serge