LP-MSPM0C1104: how to output pwm low in default

bill.liao

Part Number: LP-MSPM0C1104

Tool/software:

Hi, experts:

I used CCS Theia 1.3.1 to set PWM configuration of 20 WQFN in LP-MSPM0C1104, I set TIMA0 as PWM source and enable all 4 channels, the PWM Period Count is set to 1000, when I use

DL_TimerA_setCaptureCompareValue to set the duty cycle, I found if I set 0, the actually duty cycle is almost 100%, and if 1000, the output is high level, but the led will be turned on at high level, so I wonder how to make it be low level in this case? Thanks.

Bill

2 months ago

0 Sal Ye 2 months ago

TI__Genius 12985 points

Hi Bill,

What the pwm mode you are using? Edge-ailgn mode or central-align mode.

Maybe you could implement force output low to finish the function:

https://www.ti.com/lit/an/slaaek4/slaaek4.pdf

B.R.

Sal

0 bill.liao 2 months ago in reply to Sal Ye

Intellectual 275 points

Hi，Sal:

I found if pass 999(1000 - 1) to DL_TimerA_setCaptureCompareValue, PWM output will be low level, can you confirm it is the correct way?

Bill

+1 Sal Ye 2 months ago in reply to bill.liao

TI__Genius 12985 points

Hi Bill,

I want to note that, if you set the pwm period as 1000, it will automatically set (1000-1) into load register to set the pwm period. So it should be correct to keep high or low (this depends on your pwm configuration) if you give CC value as 999.

B,R,

Sal

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LP-MSPM0C1104: how to output pwm low in default