topic imxrt1024 flexpwm PWM_X in i.MX Processors

imxrt1024 flexpwm PWM_X

po-pony — Fri, 28 May 2021 07:29:19 GMT

Hi,

I am using the FlexPWM of imxrt1024 to generate PWM. There is no problem with PWM_A and PWM_B channels, but there is no PWM output when I using PWM_X. I see that some people have asked this question in the post, but no one make it clear and there is not a solution.

I used MCUXpresso config tools to configure the pins as PMW_X function. I also found that in the peripheral configuration, both channel A and B can select the PWM function, but the X channel does not have this option. In the official SDK, the PWM_SetupPwm function does not seem to be able to configure PWM_X.

Can anyone explain what is going on?

Thanks.

Re: imxrt1024 flexpwm PWM_X

gusarambula — Mon, 31 May 2021 22:37:14 GMT

Hello po-pony,

I looked for other threads regarding this topic and it seems that there are confusions in regards of the PWM_X pin.

There are only two FlexPWMs on the i.MXRT1024. The PWM_X is not an independent signal, it is an accessory signal, it's rising edge and falling edge are controlled by the VAL0 and VAL1 registers.

PWM_X pin can also optionally output a third PWM signal from each submodule. However, this function is apparently not enabled on the SDK driver, only capture is available.

You can find how this is setup in Figure 50-2 PWM Submodule, on the i.MXRT1024 Reference Manual.

I hope that this information helps!

Regards,
Gustavo

Re: imxrt1024 flexpwm PWM_X

po-pony — Tue, 01 Jun 2021 01:26:36 GMT

Hi Gustavo，

This is the clearest explanation about PWM_X so far. Your info help me a lot, thank you very much.

Regards,
po-pony