The 3-channel, 120 degree, Phase-Shift PWM project found HERE -- is now using updated Code. I added center-Pulse marker Interrupts and a Sync marker for testing start-up behavior. A major change is the waveform generator Timers now use Phase-PWM mode-10.
| Created: Sep 17, 2022 Updated: Sep 17, 2022 |
1. Very nice site, my congratulations for the initiative
2. I have a question related to the 6 channel phase shift project, what is the maximum pulse frequency able to run on Arduino UNO R4 Minima/wifi, the clock there is set to 48Mhz
Hi Enrique,
My sincere apologies for responding so late!!!! My site is supposed to alert me to new posts (including comments) but I didn't get any notification for your post. So, I didn't know it was there.
I did try to contact you via email near the day you joined but heard nothing back. Probably hit your SPAM filter...
But to answer the question, not very high freq in 6-chan PSPWM, maybe the max 600 Hz shown. Because I use a time delay to realize phase-shift, higher frequencies are more difficult to set accurate using delayed start.
Another tactic exists using TCNT offset. I've got a project running here for 4-channel 90 degrees that works up to 80 kHz with (IMO) 'accurate' phase shift. Unfortunately, my tools are low-cost and I do all the work on a little table in my apartment.
I haven't yet published the 90 degree project. And I haven't yet attempted doing 6-channel 60 degree PSPWM using the TCNT offset approach. I can tell you these type projects are meant to be Fixed-Phase-Shift at Fixed Frequency. The variable you can change is the duty-cycle which may not be what you're looking for. Worse still, using these type Timers for PWM you run into duty-cycle resolution becoming (a larger-step size) as frequency increases. For example, my current project of 4-90's PSPWM at 80 kHz has duty-cycfle steps of 1%. That's pretty big and likely not what a lot of application projects would need -- IDK for sure.
As for using a Arm® Cortex®-M4, I don't know that MCU, not familiar with its Timer(s) so I suspect my project code won't even compile...
So, again, very sorry for the poor response. I wouldn't have found this missed comment at all if Google's spider hadn't left a lot of info in my logs about a problem on this post. Hope this info finds you and helps out.
best wishes,
Lee