I'm trying to produce a stable clock output that is steady, in free-running mode. Presently I'm not using any triggering, simply setting up a single DIO line to be type Clock, PP output, Continuous mode. What I'm getting is a square wave output that is not stable - it 'shifts' periodically as if Patterns is outputting an expected sequence of nice clean square waves, then resetting, and then outputting another good sequence of square waves. How do I set this up to produce output that is totally stable, without the periodic 'hiccups'?
My goal is to produce a digital pattern consisting of 8 channels, each as PP output, each executing at its own specific frequency, and synchronized to line 1 as the clock line. And without any instability in any of the outputs. If this needs to be done in some mode other than free-running, with the use of a trigger input, that's ok. But the tutorials and manuals don't seem to cover what I'm trying to do in enough detail.
Additional info: On the scope (whether Digilent or literal instrument) the output of any Patterns DIO line is a square wave that exhibits nasty spikes protruding above the rising edge and below the falling edge. These spikes are about 15% to 20% of the amplitude (3.3v) of the square wave, which wave exhibits a significant amount of jitter. This is with the output of the DIO line connected only to the scope input (and connected to nothing else) via a short wire. These spikes can be easily seen when using the 500mv vertical sensitivity setting on the scope. The jitter is easily seen when you set the scope trigger level so low that the scope does not trigger on the waveform. In a stable waveform, you should see a smooth motion of the waveform horizontally, not the severe jitter I'm seeing. And when the scope trigger level is set so that the scope does trigger on the waveform, the jitter is still apparent, though much less violent, as the vertical portions of the trace render a few line widths across and look blurred as the waveform jitters back-and-forth visibly.
Update: based on other posts which talked about jitter, I downloaded the latest version of the Waveforms application and the problem appears to be mostly resolved. However, there is still some jitter present at lower frequencies, though it is much less noticeable. It would be really important to get this totally resolved, but I think I can deal with it for now. The nasty spikes protruding from the rising and falling edges are completely gone - that's likely the biggest issue for my test setup.
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CalamityHowler
I'm a Patterns newbie.
I'm trying to produce a stable clock output that is steady, in free-running mode. Presently I'm not using any triggering, simply setting up a single DIO line to be type Clock, PP output, Continuous mode. What I'm getting is a square wave output that is not stable - it 'shifts' periodically as if Patterns is outputting an expected sequence of nice clean square waves, then resetting, and then outputting another good sequence of square waves. How do I set this up to produce output that is totally stable, without the periodic 'hiccups'?
My goal is to produce a digital pattern consisting of 8 channels, each as PP output, each executing at its own specific frequency, and synchronized to line 1 as the clock line. And without any instability in any of the outputs. If this needs to be done in some mode other than free-running, with the use of a trigger input, that's ok. But the tutorials and manuals don't seem to cover what I'm trying to do in enough detail.
Additional info: On the scope (whether Digilent or literal instrument) the output of any Patterns DIO line is a square wave that exhibits nasty spikes protruding above the rising edge and below the falling edge. These spikes are about 15% to 20% of the amplitude (3.3v) of the square wave, which wave exhibits a significant amount of jitter. This is with the output of the DIO line connected only to the scope input (and connected to nothing else) via a short wire. These spikes can be easily seen when using the 500mv vertical sensitivity setting on the scope. The jitter is easily seen when you set the scope trigger level so low that the scope does not trigger on the waveform. In a stable waveform, you should see a smooth motion of the waveform horizontally, not the severe jitter I'm seeing. And when the scope trigger level is set so that the scope does trigger on the waveform, the jitter is still apparent, though much less violent, as the vertical portions of the trace render a few line widths across and look blurred as the waveform jitters back-and-forth visibly.
Update: based on other posts which talked about jitter, I downloaded the latest version of the Waveforms application and the problem appears to be mostly resolved. However, there is still some jitter present at lower frequencies, though it is much less noticeable. It would be really important to get this totally resolved, but I think I can deal with it for now. The nasty spikes protruding from the rising and falling edges are completely gone - that's likely the biggest issue for my test setup.
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