In SX Microcontrollers, SX/B Compiler and SX-Key Tool, Dr Now wrote:

I'm working on a project where an SX controls an A/D chip.  This A/D chip requires a 10 MHz clock signal, and every 8192 cycles of this A/D clock the SX provides a signal to the A/D chip. For reference, the SX is currently running at 50 MHz.  The SX signal (pin going HIGH or LOW) needs to be synchronized to within 10 nano-seconds of a pulse from the 10 MHz clock.  The SX counts the external clock using the RTCC.  Flip-flop circuitry is then used to synchronized the rising or falling edge of the SX signal with the rising edge of a 10 MHz clock pulse.

My thought is that it might be possible to do this all with only one clock, running at 10 MHz, instead of one clock for the SX, and one for the A/D.  It would also be nice if the flip-flop was not needed to synchronized things. 

So, my question is:   when do SX events occur relative to the SX clock signal?   Specifically, when the SX takes a pin HIGH or LOW, does this occur 'with' a clock pulse, or at some other time?  If it is 'with' a clock pulse, how close in time is the pin signal to an SX clock pulse?

One easy way to check this would be with an oscilloscope.  Unfortunately, mine doesn't go fast enough to resolve events at the nano-second time scale.

Can anyone help with these SX details?

Thanks

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