macOS just updated to 11.2.2 (at least I think that's the change responsible), and now if I try to build from the icon at the bottom of the VS Code window, I get an immediate failure:

> Executing task: espressif.esp-idf-extension: ESP-IDF Compile <

ESP-IDF Custom Terminal
$ cmake
spawn cmake ...

Do you have the C/C++ Extension installed?

I'm struggling to remember what I did to fix this, but I believe it's a matter of letting or making the C/C++ extension use build/compile_commands.json to find the proper include path.

compile_commands.json is available after you've done your first build.

Not quite sure what's going on here - using "stable", v4.2. The esp32s2 only has 4 PCNT units - but I'm not building for the esp32s2, I'm building for the regular old esp32, which has 8 units.

Test case: build examples/peripherals/pcnt
Builds fine, presumably works (haven't tested that far)

Now ...

Yep, the light just dawned this morning and I was back to reply to myself... and you beat me by 2 minutes.

Hi there!

I'm trying to update some sources from the v3.3.4 esp-idf to v4.2.0 - need to get the v4.2 tools set up first.

Following the Getting Started guide: https://docs.espressif.com/projects/esp-idf/en/stable/esp32/get-started/index.html

When I run install.sh, it fails during the installation ...

I've been trying to use (possibly mis-use) the LEDC PWM generators as general waveform generators.

I've run into an instance where setting up 1 high-speed channel and 1 low-speed channel at a low frequency results in no output on the low-speed channel. This has been super frustrating, because I've ...

Wouldn't you get more accuracy by using a hardware signal to gate the counter?

Like... using a 5Hz signal from the LEDC, fed to a GPIO that's also used as the counter gate. Then it's just a matter of adding an interrupt routine on the negative edge of the gate signal to grab the count.

I've had to ...

Some interesting trade-offs using this as a waveform generator.

If you use an RTC clock divider of 1, you get lovely smooth waveforms, but you can only generate multiples of ~131.6Hz (at least on my board). Waveforms up to the 500kHz range look pretty decent.

If you use an RTC clock divider of 8 ...

I'm looking at the esp32 Technical Reference Manual, section 28.5.4, and it says:

A phase-shift of 0 / 90 / 180 / 270 degrees can be added by setting register SENS_SAR_DAC_INVn[1:0].

Do you think this is just a documentation error? My experimentation with the invert values has discovered useful ...