Understanding Synchronous PWM

[ahuberee]

Hello,
I have a project that I am working on where I would like to have two separate PWM outputs (CH0 and CH1 or Pins 34/35 and 36/37 respectively).

Everything is working well, except for when I try to make the Channels Synchronous. It seems like CH1 takes on the same Period as CH0, but it updates the Duty correctly.

I thought that "Synchronous" describes an update synchronicity that would update the output on the Next Period of the respective channel cycle to reduce occurrence of jitter. The period and duty would be updated at the same time on event (depending on the Update Mode). That each independent channel could be updated with different rates but the change in output would only occur if the buffer registers are loaded and it receives the update command, say (MODE0).

So, is Synchronous instead describing that both channels are using the same clock with same period? Do I have any cause for concern of updating clocks separately that may produce jitter or is this handled by the SAM3X chip?

[ahuberee]

I was able to set my scope up to trigger on Two rising edges within a time window. I wanted to see if there were any issues of chopped Square wave when making Asynchronous changes. I changed period/duty at least a hundred times and it appears to complete one cycle before making changes to the output. This leads me to believe that the chip is handling changes properly without creating jitter / chopping the output.