Kaiser,
For normal sweep speed, (via the smSetSweepSpeed function) the resolution on which we can change the GPIO output is multiples of 39.0625 MHz. (N * 39.0625 MHz) If you are using the fast sweep speed, that number is 156.25 MHz but can be offset by a multiple of 39.0625 MHz. (N * 156.25M + 39.0625M * [0,1,2,3 depending on factors]) If you use the same sweep settings, the API will be consistent about what LO steps it changes the GPIO on.
I believe the logic is, that if your GPIO freq exceeds the freq calculated from the equations above, then we perform the switch. If you use these multiples directly, pick a number slightly higher to force the switch.
It sounds like you just need to nail this down for just a couple sweep configurations? This should be enough information for you to start adjusting the frequency on the GPIO steps and choosing the best values for your sweeps?
Regards,
Andrew
