Klipper ADXL345 Standalone MCU Case

thingiverse

A simple case for an ADXL345 and WaveShare RP2040-Zero https://www.waveshare.com/wiki/RP2040-Zero with an interface adaptor that guides wiring. I used 2 pins to attach power and ground from the ADXL345 to the RP2040-Zero and then four solid core breadboard jumper wires bent into shape following the guides in the interface layer. Not all holes need to be drilled out - generally one hole per wire needs drilling - but it doesn't hurt anything if you do. Only GND, 3.3v and pins 0-4 are used on the RP2040-Zero. The adxl345.cfg file is a template to use with your board. The specific device ID of your RP2040 MCU needs to be substituted into the file. I recommend putting the file onto your RP2040 so you have it with you whenever you have the device - this is why the Boot button is accessible through a hole in the case. Follow Klipper directions for flashing a new firmware on the MCU and flashing it. Once you've set the device id correctly, add [include adxl345.cfg] into your printer.cfg anytime you want to calibrate resonance. Comment it out when you are done or you will be required to have that MCU constantly attached. I bought a 10ft USB-A to USB-C cable from Amazon which works great. I do not see any impact on resonance values from the cable or the attached accelerometers/MCU. The case is made to take a press fit M4 bolt so that on a bed slinger you can attach it to a bed screw. The smaller holes fit M3 screws and can attach to a 4010 fan mount (the spacing is correct for 2 screws).