Dual ADXL345 on a bed-slinger?

General Discussion
1

Basic Information:

Printer Model: Ender 3
MCU / Printerboard: BTT SKR Mini E3 -v- 3.0
Host / Raspberry Pi 4B, 2GB
klippy.log (13.5 KB)

klippy.log

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Describe your issue:

I’m installing an LDO Nitehawk 36, mainly to reduct the amount of wiring running to the hot end. It uses the USB bus for data and commands, which is a much simpler setup than CANbus. The toolhead has an integrated accelerometer (adxl345), so that takes care of the X-axis, but I still need to cover the Y axis.

I’m planning to install a second ADXL345 on the bed (permanently, using only when needed), connected to a Raspberry Pi PICO board, and connecting the PICO to the Pi 4. Unless that’s unnecessary and/or overkill, and I should wire the second ADXL345 directly to the Pi 4 using the GPIO header?

My question is: since the USB bus is already handling the X-axis adxl345, can I still use the USB bus to connect the PICO to the Pi 4 (and will Klipper be able to keep the two straight {and/or what needs to go into the config file to enable this?}), OR should I keep the two separate (if this is needed) by connecting the PICO to the Pi 4 using the GPIO header pins?

If anyone could steer me towards a good writeup of what’s needed to do this (or answer it here), I’d very much appreciate it!

2

There is no right or wrong here:

Note that the ADXL345 can be finicky to wire and prefers 17-times shielded cables with gold plated wires and not longer than 0.2 mm. Also you need to feed it only in blue-moon nights.
As such, the integrated solutions like the last example have a certain merit.