Newbie struggling with Complimentary Output of Timer

[joeaverage]

Hi,

first foray into STM32 with a Nucleo-F7222ZE.

Using CubeMX I have set up Timer1 to generate PWM. I can get outputs OC1, OC2, OC3 etc, but I cannot get the complementary outputs OC1N, OC2N, OC3N to operate.

I feel like I'm missing something, like dead band between OC1 and OC1N for example..

I've tried just about every combination I can think of in CubeMX, with no result so far.

Craig

[TDK]

Did you try HAL_TIMEx_PWMN_Start? Show your code.

Here's a working example:

STM32CubeF7/Projects/STM32756G_EVAL/Examples/TIM/TIM_ComplementarySignals/Src/main.c at 99ad6215a6bd8101a4981137f4a2f06c69e29d37 · STMicroelectronics/STM32CubeF7

[joeaverage]

Hi,

thanks for your reply, and I rather think you are on to it. I have used this:

HAL_TIM_PWM_Start(&htim1,TIM_CHANNEL_1);

to start the timer. Your reply suggests I need to start the complementary output specifically. I'll try it. 

Thanks

Craig

[joeaverage]

Hi, I have tried:

HAL_TIM_PWMN_Start(.....

HAL_TIM1_PWMN_Start(

and  get compile errors whenever I try to include either the timer number (1) or the  'N' for complementary

Craig

[TDK · Accepted solution]

The correct function to use to start a complementary channel is HAL_TIMEx_PWMN_Start. For example, to start channel TIM1_CH2N:

HAL_TIMEx_PWMN_Start(&htim1, TIM_CHANNEL_2);

> HAL_TIM_PWMN_Start

> HAL_TIM1_PWMN_Start

Neither of these are functions that exist in HAL. Perhaps copy/paste to avoid typos.

[joeaverage]

Hi, 

that worked, but I am now confused, I read this in the HAL documentation:

HAL_TIM_PWM_Start(...... and that seems to work to start the OC1 output while

HAL_TIMEx_PWM_Start( ........ gives an error.

Why is it I use one syntax to start OC1 and another to start OC1N? I can find no mention in  the HAL documentation about this other syntax. Do I have the best available Hal documentation:UM1905

Craig

[joeaverage]

Hi,

I've found the Timer Extension Driver chapter......so it is included in the documentation that I had, but that I was not looking far enough afield to find it.

Thanks for your help.

Craig

[TDK]

> HAL_TIMEx_PWM_Start( ........ gives an error.

This is not a HAL function and therefore does not appear anywhere in UM1905.

The correct function to use is still HAL_TIMEx_PWMN_Start, which appears in UM1905.

[joeaverage]

Hi, 

yes, thanks I have found the relevant section. New syntax is confusing to start with.

Craig