IR Bed Probe with ADXL345 for Input Shaping

Enjoy Input Shaping on your Positron V3 with a combined IR Bed Probe and ADXL345 accelerometer.

This probe is a drop-in replacement for the original.

Officially Verified by Positron3D.

Cables included.

Specification

• IR differential probe
• Uses first row of three pins for power and output signal
• Input voltage 5V

• ADXL 
• Uses second row of four pins to communicate via SPI
• powered from 5V provided by the connection to IR probe (using step down convertor)

• Accessory
• Cables are measured for Positron V3
• Pin headers are not key therefore pay attention to have proper orientation of cable connectors.
• IR cable length 60cm 
• ADXL cable length  70cm 

• PINs
• O -  Output
• G - Ground/Negative
• V - Voltage 5V
• SC - SCK
• MO - MOSI
• MI - MISO
• CS - CS

IR probe limitations

• IR probe works on transparent glass, but in case that there is something else on the back side of the glass it will detect such a surface instead. In case reflection from it is stronger than reflection from the front glass surface. Therefore the probe works best on ITO bed that is fully transparent. In case you want to use it on bed with a kapton heater. Make sure that the back of the glass is painted to be black and opaque.

Installation of ADXL

• If you are not using RPi TFT display you can follow this link
• In case you are using RPi TFT display you have to add extra Chip Select pin to the GPIO link the RPi breakout board is using GPIO pin number 29