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10 years, 5 months ago.
After what delay will a PWM/ticker square wave output its first rising edge?
I'm trying to make a digital Phase lock loop using an mbed LPC1768 to lock the phase of a PWM or ticker generated square wave to an external GPS 1pps source.
Is there a known time delay in the hardware as to when the PWM or ticker wave will output its first rising edge so that I can use the delay to accurately match up the phases?
Thanks
1 Answer
10 years, 5 months ago.
With Ticker I guess you use a DigitalOut, which iirc has a delay of something like 70-80ns. The LPC1768s PWM iircs updates its values at the end of each period. The rising edge is when a new period starts, but if you just use PwmOut that is not defined, it just happens when it happens.