After a few days of trying to get the complimentary outputs on the STM32F103 Nucleo going I’ve finally succeeded. It was surprisingly simple in the end but there is a general lack of documentation and I wonder at the completeness of the PWM API. Anyway, here is a platform specific working example. It produces a two channels of complimentary output signals (i.e. 4 outputs in total) running at 1kHz with 80% duty and an deadtime of about 13.5uS.
#include "mbed.h" DigitalOut my_led(LED1); /* Pin mappings for Timer 1 (the advanced timer with deadtime) From: https://developer.mbed.org/users/mbed_official/code/mbed-src/file/a11c0372f0ba/targets/hal/TARGET_STM/TARGET_STM32F1/TARGET_NUCLEO_F103RB/PeripheralPins.c {PA_8, PWM_1, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, 0)}, // TIM1_CH1 - Default {PA_9, PWM_1, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, 0)}, // TIM1_CH2 - Default {PA_10, PWM_1, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, 0)}, // TIM1_CH3 - Default {PB_13, PWM_1, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, 0)}, // TIM1_CH1N - Default {PB_14, PWM_1, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, 0)}, // TIM1_CH2N - Default {PB_15, PWM_1, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, 0)}, // TIM1_CH3N - Default */ int main() { PwmOut PhaATop(PA_8); PwmOut PhaABtm(PB_13); // This should be the complement of PA_8 PwmOut PhaBTop(PA_9); PwmOut PhaBBtm(PB_14); // This should be the complement of PA_9 PhaATop.period_ms(1); PhaATop = 0.8; PhaBTop.period_ms(1); PhaBTop = 0.8; TIM1->CCER |= 4; //enable ch1 complimentary output TIM1->BDTR |= 0xff; // specify the maximum amount of deadtime required approx 13.5us - see page 356 of reference manual TIM1->CCER |= 64; //enable ch2 complimentary output TIM1->BDTR |= 0xff; // specify the maximum amount of deadtime required approx 13.5us - see page 356 of reference manual while (1) { my_led = !my_led; wait(0.2); // 500 ms } }