can change clock velocity during sending video data to VIP

Troy huang

Dear Folks and TI specialist:

I want to confirm VIP usage method.

Currently, our system must use function like flywheel and video clock velocity will be changed and no glitch generation. Example:74.175=>74.25MHz.

So I want to know whether the condition can be accepted for VIP port. Clock will first stop to low, wait some time(it should be a small time) and then continue sending clock to VIP.

The condition waveform is as below.

over 11 years ago

0 Brijesh Jadav over 11 years ago

TI__Guru**** 477705 points

Hi Huang,

It should work mostly, but sometimes, vip overflows, you just have to reset vip port in this condition.

Regards,

Brijesh

0 Troy huang over 11 years ago in reply to Brijesh Jadav

Prodigy 110 points

Dear Bijesh:

I want to know why VIP overflow will be occured since we use flywheel function. I think 8148 should continus receive video data seamless.

Regards

Troy

0 Steve Clynes over 11 years ago in reply to Troy huang

TI__Mastermind 43875 points

Clock stretching like this is fine as long as the active data stream is compliant with the configured format etc...

BR,

Steve

0 Troy huang over 11 years ago in reply to Steve Clynes

Prodigy 110 points

Dear Steve:

Thanks for your explanation so only active data stream is compliant with the configured format, the VIP overflow condition will not be occured. Is it right?

B.R.

Troy

0 Steve Clynes over 11 years ago in reply to Troy huang

TI__Mastermind 43875 points

It shouldn't cause an issue. Only data on the active edge is considered.

BR,

Steve

Processors

Processors forum

can change clock velocity during sending video data to VIP