6 years, 5 months ago.

Nucleo F411RE: Cant get PC_14 and PC_15 to work?

Hello,

I'm trying to work with a Nucleo F411RE board but I can't seem to get pins PC_14 and PC_15 working as digital outs.

I have PC_7, PC_10, PC_11, and PC_13 working just fine but 14 and 15 do nothing. Is there something I'm missing about these pins? Do they have some kind of special purpose and cannot be set to digital out?

FYI, I am fairly new to Nucleo boards, or anything more sophisticated than an Arduino to be honest.

Code is very simple:

  1. include "mbed.h"

BusOut RGB1 (PC_7, PC_10, PC_11); BusOut RGB2 (PC_13, PC_14, PC_15);

int main() {

RGB1[0] = 1; reads 3.3V RGB1[1] = 1; reads 3.3V RGB1[2] = 1; reads 3.3V RGB2[0] = 1; reads 3.3V RGB2[1] = 1; reads 0V RGB2[2] = 1; reads 0V return 0; }

1 Answer

6 years, 5 months ago.

Please use <<code>> and <</code>> tags on separate lines for posted code to keep it readable.

PC_14 and PC_15 have a double function as real-time clock crystal oscillator for the F411. Check your board: is there a Xtal mounted near the processor (Position X2). In that case the pins should not be available on the morpho connector. In case there is no Xtal you have to check solderbridges SB48 and SB49. They should be closed, but will be open by default. PC_14 and PC_15 will not be connected to morpho connector in case the solderbridges are open. This info is in the user manual, but does not show up on the board page here

Accepted Answer