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PWM Timer Slave not getting triggered by Master

Xxoyo.1
Associate III

Hello, I am trying to set timer 3 as a master to timer 1 without success.

Timer3 is outputting the PWM correctly, but timer1 is not getting triggered by Timer3's PWM Signal. What else am I missing?

My board is STM32F429 discovery

Here are my settings timer settings:

Master (Timer 3) Pwm Frequency = 10Hz, Pulse Width 40% of Arr

Slave (Timer 1) Pwm Frequency = 5000Hz, Pulse Width 50% of Arr

Timer1 is triggered by Timer3 using Gate Trigger:

0693W00000Bc447QAB.png0693W00000Bc442QAB.png0693W00000Bc44CQAR.png 

Blue line is timer 3 , which is outputting 10Hz Correctly

0693W00000Bc455QAB.png 

Update: :After doing more test with the Settings, I finally found that the trigger out event in Timer3 should actually be OC1REF. I got the wave form I wanted, however I dont know why the duty cycle in the first pulse of TIMER 1 is wrong. See picture (Purple line: first pulse width is longer than the other's)... Anyone know why / how to fix this?

If anyone interested , I can email you the source code :), I just hope to solve this problem!

0693W00000Bc4XsQAJ.png 

Update 2: Problem solved. Fiddled with the settings and gone through a trial & error process , finally got the waveform i wanted

3 REPLIES 3

TIM1 without Gate mode works properly?

Read out and check/post both TIM and relevant GPIO registers content.

JW

if TIM1 is not config as slave mode, it is able to produce the 5Khz pwm signal.

so I haven't missed any obvious codes? Like needing to enable something etc?

Read out and check/post both TIM and relevant GPIO registers content.

JW