Inky Impression 7.3" with a pico 2W (circuitpython)

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I have an rpi Pico 2W working with an Inky Impression 7.3" (2025).

I wired the Inky directly to the Pico and based the code on bablokb’s very helpful circuitpython examples/driver

It works very well. However, I’m having difficulty running my setup off a battery, in particular, getting the onboard timer/‘RTC’ to function in circuitpython. The alarm module is not available in circuitpython for the Pico 2W, so I’ve been trying light sleep (time.sleep()). However, once put to light sleep, the pico does not wake up under battery power.

bablokb has a patch “RP2xxx Low-Power” which provides a working light-sleep/deep-sleep for the Pico 2W. I built a version of
circuitpython with this patch, tested it, and my pico (light and deep) sleeps fine.

However, I’m somewhat stuck. The time/alarm patch is for version 9.2.7 of circuitpython, while it seems that (EPaperDisplay) support for spectra6 displays was introduced in version 9.2.8.

Any suggestions on what I might do here? This is my first circuitpython project, so I’m still feeling my way around.

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Hm, have you tried the patch with 9.2.8? It should work. If not, please open an issue in my repo and I will fix it. I am sure I am running a 9.2.8-patched system, but my build system is a bit different.

While you are at patching: I would recommend also that you apply the acep_no_clean.patch. This speeds up the refresh considerably.

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Patching 9.2.8 worked a treat!

I wasn’t paying attention when I originally tried to apply the patch to main / most recent version, and then reverted to 9.2.7

Thanks for that and the pointer on the clean cycle for ACEP displays: will it work as is for a spectra6 display?

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Regarding refresh, ACEP and Spectra6 displays use the same code, so both will profit from the patch.

Just a note regarding switching branches on CircuitPython: I always use

git switch --discard-changes --recurse-submodules branchname

when I switch between main and a 9.2.x branch. The reason is that main has a number of different submodule versions and this prevents mixing up things.

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That works well; thanks again for the very helpful pointers.

With the ACEP no clean patch, time for a display ‘refresh’ has now dropped from 39.7s to 20.2s !

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@bablokb - i’m getting the sense that (in response to my question on the other thread), the inky-frame firmware (Release Version 1.26.1 · pimoroni/inky-frame · GitHub) cannot be used on this setup of a pico2W with the inky impression, and that one should instead use your circuitpython-inky firmware…

would you or @simer mind sharing a pinout/wiring diagram showing how to properly jumper wire the pico 2w to the inky impression?

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I am using one of my adapters (see GitHub - bablokb/pcb-pico-pi-base: An Interface PCB to use Pi-Hats with a Pi-Pico(w)). In the repo, you will find a file “mapping.ods” that will give you a number of suitable pin-mappings. The Pico is very flexible regarding I2C and SPI, the Pi isn’t. But you mainly route Pi-I2C to some Pico-I2C pins and Pi-SPI to Pico-SPI.

You might want to try Pico to Pi HAT - The Pi Hut, which is a similar adapter (with a different mapping). I don’t have it and I don’t know if it works, but since you basically only need I2C, SPI and a bunch of GPIOs I don’t expect problems.

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Thanks! Took a few hours but was able to get the Pico 2W working with the inky impression and your circuitpython based firmware. I used jumper wires but will be testing out the Pico to Pi HAT when I get home in a few days.

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