I've tested a setup here with a square wave (500mHz or slower, 5Vpp with +2.5V offset) using a version of PicoScope 6 that will be released shortly and can confirm that the pulse width trigger does work with the condition specified.
Example of Pulse Width Trigger
The new version will be available via our Software Downloads page (http://www.picotech.com/software.html) or you will receive an alert via the PicoScope 6 software if you have enabled the appropriate option in the Updates tab of the Preferences dialog.
Hi, I am having a pulse-width trigger problem as well, with channel D on a Pico 3405A.
If I use the onboard signal generator maxed at a 2V 1 MHz square wave fed into channel A, I can see the triggering stop if I increase the pulse width beyond 500ns. Just fine.
Unfortunately, I am trying to observe a faster signal on channel D, and it only triggers when the pulse width is set to 0 (zero).
I am trying to observe a serial binary signal which is sometimes a single high bit, and sometimes two high bits in a row, operating at around 3 MHz. In other words, sometimes the pulse is one clock cycle (about 300 ns), and sometimes it is two cycles (about 600 ns). Here are some images to help explain.
First there is short_pulse.png, which shows the short pulse of about 300 ns.
The shorter pulse
Then there is long_pulse.png, showing the longer pulse, about 600 ns.
The longer pulse
Finally, there is no_trigger_4ns.png, showing how the trigger doesn't occur even with a "greater than 4ns" setting.
Pulse width trigger set to greater than 4ns, no trigger occurs
I expect that I should be able to set to pulse width triggering around "greater than 500 ns" and the trigger occur only on the longer pulse. Unfortunately the trigger never occurs. There is a lot of ringing on the signal, but that ringing is all above the trigger threshold and shouldn't be a problem. I also tried a window pulse width, setting "dwell inside" to cover the entire ringing amplitude, and it doesn't work either. Is help available for this issue?
Hi, and thanks for the rapid engagement. I really appreciate that.
It seems like using another channel on the same signal allows the pulse width trigger mode to function correctly, so perhaps the problem is unique to channel D.
I have moved on to other modes of testing which do not rely on the pulse width triggering, but I still look forward to PicoScope software and driver updates.
I found a(nother) bug in the Advanced Trigger Menu “Pulse Width” for digital inputs (D1/D0) . If I try to trigger for a Pulse Width greater than 20 ms on a digital input (D1). The Oscilloscope triggers always.
But the pulse width is less than 5ms.
My digital signal channel settings are correct: (Signal is TTL 3.3V high)
For analog signals e.g. A/B everything works fine.
SW versions: PicoScope® 6 - PC Oscilloscope software version: 6.11.4.929 and 6.10.16.2
There was an issue relating to pulse width triggering on digital channels that was reported and fixed recently. This should be available via the next version of PicoScope 6.11 Beta.
If you have a PicoScope 6 settings file corresponding to the trigger setup, please post it here or send to support@picotech.com and we can take a look.