Need help on a 3Hz PWM | Cypress

Need help on a 3Hz PWM

Summary: 2 Replies, Latest post by douglaslps on 20 Sep 2010 09:01 AM PDT
Verified Answers: 0
Last post
Log in to post new comments.
douglaslps's picture
User
2 posts

Hi guys,

this is my first post in this forum.

I have some C language experience and I'm facing some problems to configure a CY8C29666 chip to generate a 3Hz PWM pulse. The minimum frequency I was able to generate was 360Hz.

Can anyone walk me through that?

Thanks,

Douglas

user_611219's picture
User
40 posts

Hi Douglas,

The CY8c29666 device is a PSoC 1 device, so your post belongs in the PSoC 1 forum.

On to your problem...

Assuming a sysclock of 24Mhz, and a wanted PWM of 3Hz, would require a divisor of 24Mhz/3Hz = 8Mhz.

VC1 and VC2 can divide by 16 each, and VC3 by 256. So, 16x16x256 = 65536. (Hold that thought)

8Mhz/65536 = 122.0703125

So, using an 8bit PWM, with a period of 122 will give you the requested 3Hz output.

In Summary:

VC1 /16

VC2/16

VC3 source = VC2

VC3/256

----------------

PWM:

Clock = VC3

Period = 122

---------------

Hope this helps.

douglaslps's picture
User
2 posts

Hi Terrence,

"The CY8c29666 device is a PSoC 1 device, so your post belongs in the PSoC 1 forum."

Thanks for the heads up.

Also thanks for your help on 3Hz PWM. Another solution would be to use internal 32kHz as clock and use period as clock (32k) divided by 3, which results a period equals to 10666.

Thanks for your help.

Regards,

Douglas

Log in to post new comments.