[sdiy] Sequencer interrupt latency?

[Speth, John]

Hi folks-

I'm finishing up a PIC based sequencer and now I'm optimizing for performance.  My step input feeds the interrupt input.  When a step interrupt is serviced, the analog out is set, then the step trigger is asserted, and finally the right LED is lit up.  My question is:

>From your experiences, what is the maximum acceptable latency from step input to analog out and step input to step trigger?

By "maximum acceptable latency", I mean that maximum time that it becomes noticeable under non-audio rate applications.  Right now, I'm getting about 50 usec latency to the step trigger which means I get maybe 40 usec to analog out.

Thanks...

John Speth - john.speth at coherent.com