PWM pausing

[developer2]

Posted on August 07, 2013 at 13:52

Hi All,

i'm using on STM32F417 PWM on TIM4 CH2, i have successfully initialized PWM, i have there LED with blinking on 2Hz, i would like to pause and i would like to return PWM to initial state with configured polarity, is it possible with one command ? when i use only TIM_Cmd( TIM4, DISABLE); the LED stays in the last state, sometimes stays lighting and sometimes stays in off state, Thank You for all replies, Kind regards ... #!telegraphing

[Tesla DeLorean]

Posted on August 07, 2013 at 14:11

TIM4->CCR2 = 0;  Would be more predictable

[developer2]

Posted on August 07, 2013 at 14:59

here is my source:

DEBUG_LED_GREEN1_TIM4CH2(x) {   if(x==0)   {    TIM_SetCompare2( TIM4, 0);    TIM_Cmd( TIM4, DISABLE);    TIM_CtrlPWMOutputs( TIM4, DISABLE );   }   else   {    TIM_SetAutoreload( TIM4, x);    TIM_SetCompare2( TIM4, (x/2==0?1:(x/2)) );    TIM_Cmd( TIM4, ENABLE);   } } still no success :( i tried:    TIM_Cmd( TIM4, DISABLE);    TIM_SetCompare2( TIM4, 0);    TIM_CtrlPWMOutputs( TIM4, DISABLE ); and also:    TIM_Cmd( TIM4, DISABLE);    TIM_CtrlPWMOutputs( TIM4, DISABLE );    TIM_SetCompare2( TIM4, 0); :(

[DAS.ANIL KUMAR]

Posted on June 20, 2014 at 09:22

I have same problem.... i used tim1 ch4 and ch3 i want to start channel3 after 1 us  or delay betwwen ch3 and ch4  of 1 us ....plz help me ..

thanks

[Tesla DeLorean]

Posted on June 20, 2014 at 13:51

The timers really don't work that way, there is a single counting element and the CCRx are just latches/comparators.

If you want to impart some phase shift of one channel vs the next, use toggle mode, however this will always give you 50/50 duty unless you actively reprogram the TIMx->CCRx values ahead of the counter.

[DAS.ANIL KUMAR]

Posted on June 21, 2014 at 08:14thank u for reply .............. how can i shift the phase  for 1 us delay.between these channel signal . which register value used for phase shift  ..i am using stvd and stm8s103.......thanks .

[Tesla DeLorean]

Posted on June 21, 2014 at 14:28

What's with the periods?

This is an STM32 forum, if you have an STM8 question post it to that forum. If I had a 72 MHz system clock, with no prescaler 1us would be 72 ticks, and to get a phase shift in toggle mode you'd advance one CCRx by 72 with respect to the other. TIM1->CCR1 = N; TIM2->CCR2 = N + 72; // modulo period as required

[DAS.ANIL KUMAR]

Posted on June 23, 2014 at 07:19

thank u sir,   i didnot find phase shift in stm8 foroum thats why i am here.........i am using 16 Mhz internal freq.  i am generating  both signal with 10us for on and 8 us for off and continue and i want to 1 us second delay between these signal  or 2nd sinal start after 1us and continue.

plz help me   thanks

[Tesla DeLorean]

Posted on June 23, 2014 at 14:47

thank u sir,   i didnot find phase shift in stm8 foroum thats why i am here.........i am using 16 Mhz internal freq.  i am generating  both signal with 10us for on and 8 us for off and continue and i want to 1 us second delay between these signal  or 2nd sinal start after 1us and continue.

plz help me   thanks

Then open a new question in the STM8 forum, the two platforms are not compatible. Failing that you'll have 2 rtfm.....