PSOC 5, Parallel Execution of two PWM Blocks

[Anonymous]

Respected members,

I am encountering a problem regarding parallel execution of two PWM blocks. For example, if I start PWM blocks with same parameters (freq, cmp, etc.)  then at oscilloscope there is always a phase-shift between two PWMs. And if I try to change the order of the execution statements (PWM_Start();) then I get negative phase-shift. Is there anyway to get rid of this phase-shift and start two PWMs with zero phase-shift? 

[HeLi_263931]

Configure the PWMs to run only when the "start" signal is active (hardware enable). Then route this signal to a control register. That way you need to activate the signal on the register, and both PWMs start at the same time.

[HeLi_263931]

(Note: I did something similar here: https://blog.hendriklipka.de/archives/2016/03/stairstep_gen_1.html )

[Anonymous]

Thanks for your response,

   

Its not working, I enabled the PWM with hardware with ControlReg but still I needed to write the "PWM_1_Start();" and "PWM_2_Start();"in main prog.

[HeLi_263931]

Yes, you need to start the components, but as long as the control register is 0 the PWMs won't start.

[Anonymous]

Its working now.
Thanks again.

[Anonymous]

how do i enable the 2 pwm outputs from same block asynchronously  ie at different times?

[Anonymous]

I think you cant:

   

Alternatively, plz refer to following application note.

   

http://www.cypress.com/documentation/application-notes/an76439-psoc-3-and-psoc-5lp-phase-shift-full-...

       

You need to add PSFB component to your project. That component will have four outputs you can use 2 out of 4 as per your requirements.