With the shortage of Raspberry Pi’s still going on I picked up a BTT Pi 1.2 instead to run Klipper for me on my 0.2 build. The initial install went smoothly and I was up and printing in no time however when I connected the ADXL cable everything went downhill until I found the proper pin mapping.
TL;DR:
Just use the following code in your printer.cfg
to be able to run input shaping on your BTT Pi
[mcu rpi]
serial: /tmp/klipper_host_mcu
[adxl345]
cs_pin: rpi:gpiochip0/gpio204
#cs_pin: rpi:gpiochip0/gpio74
spi_bus: spidev1.1
[resonance_tester]
accel_chip: adxl345
probe_points:
59, 59, 20
Long(ish) Version
Hardware
If you are new to ribbon cables like I am be sure to have the blue side facing you or AWAY from both the Toolhead Picobilical and the Pi Hat. There is a little pull out lever that should allow you to easily put the the ribbon cable in.
![BTT Pi 1.2 with Picobilical Hat](https://drkpxl.com/wp-content/uploads/2023/05/BttPi12-771x1024.jpeg)
OS Updates
You will need to activate SPI in the BTT Pi 1.2 config file and restart the printer completely in order to enable Input Shaping
The lines to add are:
overlays=spi-spidev
param_spidev_spi_bus=1
param_spidev_spi_cs=1
param_spidev_max_freq=1000000
To the following file: /boot/BoardEnv.txt
Klipper Config
Simply add the code above, restart and run a `query_
accelerometer` to which you should get some values and from there you can just follow the bog standard Klipper instructions.
I know the group of people who build their own Voron and use a BTT Pi are very small but I hope this saves them a few hours of poking around.