multiple PwmOut pins

[Gavin Perry]

Does the mdot mbed support multiple PwmOut channels?
I’d like to set up 4 channels (RGBW) like this:

#include “mbed.h”
PwmOut ledR(PA_8);
PwmOut ledG(PA_9);
PwmOut ledB(PA_12);
PwmOut ledW(PA_11);

//I’m ok with them all sharing the same timer/period.
ledW.period_ms = 2;
//Then set the color fraction as needed
ledR = 0.01f;
ledG = 0.3f;
ledB = 0.4f;
ledW = 0.0f;
//(more programatically of course sending colors from the Conduit…

[Mike Fiore]

Gavin,

PeripheralPins.c in the mDOt platform support lists all the pins that are PWM capable.

https://github.com/mbedmicro/mbed/blob/master/libraries/mbed/targets/hal/TARGET_STM/TARGET_STM32F4/TARGET_MTS_MDOT_F411RE/PeripheralPins.c

I did some reading on this and it sounds like pins that are run by the same timer must have the same frequency, but each can have a different duty cycle (just FYI since you said you were OK with this).

PA_12 is not listed as a PWM capable pin, so you’ll need to find a replacement for that one.

Hope this helps!

-Mike

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