Continuing #367 "Triggering at sig. gen. freq" with a cleaner file history #390
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Just for what it's worth, the signal gen runs from a 1MSPS DAC, and at higher frequencies the waveform reduces in resolution to compensate. At higher frequencies I'd expect quantisation noise by itself to get to something like 5% of the period of a waveform. |
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I think I correctly handled
but I should double check.
Can you please elaborate? Say a single period of the waveform gets produced over the course of 2^10 clock cycles and a single 'scope sample is collected every 2^3 clock cycles. If you then add a trigger point every 2^7 'scope samples, shouldn't that keep the waveform steady on the screen? |
@brentfpage are we ready to merge? |
@mi-hol I'd prefer to spend a bit more time trying to improve the performance at >25 khz |
@brentfpage that is at best signaled to others via setting the PR to "draft" status by clicking on "convert to draft" link. 
I've applied that for you. As soon as it's ready from your view just remove "draft" status by pressing |
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@mi-hol Ah OK thanks |
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Added new trigger type options, Sig. Gen. Ch1 and Ch2 , that set the trigger frequency equal to the respective sig. gen. frequencies. In these modes, there's no need to adjust the trigger level to get the waveform steady on the screen. The feature gets finicky above ~25 khz or so, especially when 'scope channel 2 is enabled. I've dug around trying to find a cause, but haven't had any luck yet. The issue only appears in a limited operating range (>~ 25 khz), is not all that common even in that range, and can usually be resolved by disabling/enabling 'scope channel 2, so imo isn't a huge demerit for the PR. Also, #288 is fixed in this PR.