# Notes CMS's Polar3D printer

- board is a Printrboard, or extremely similar derivative
- bootloader is LUFA CDC, and can be programmed with AVRDude

  ```bash
  # read flash/firmware
  avrdude -c avr109 -P /dev/ttyACM0 -p at90usb1286 -U flash:r:firmware.hex:i
  # read EEPROM
  avrdude -c avr109 -P /dev/ttyACM0 -p at90usb1286 -U eeprom:r:eeprom.hex:i
  ```

- original firmware appears to be a modified version of Marlin, maybe https://github.com/Polar3D/Polar-3D-Firmware (see dumped firmware in [./original-firmware](./original-firmware))

- Parameters from existing firmware, via `M503`:
  - Steps per unit: M92 X80.52 Y41.48 Z3200.00 E100.40
  - Maximum feedrates (mm/s): M203 X350.00 Y500.00 Z350.00 E1000.00
  - Maximum Acceleration (mm/s2): M201 X1000 Y1000 Z100 E3000
  - Acceleration: S=acceleration, T=retract acceleration M204 S1000.00 T3000.00
  - Advanced variables: S=Min feedrate (mm/s), T=Min travel feedrate (mm/s), B=minimum segment time (ms), X=maximum XY jerk (mm/s), Z=maximum Z jerk (mm/s), E=maximum E jerk (mm/s) M205 S0.00 T0.00 B20000 X10.00 Z0.40 E5.00
  - Home offset (mm): M206 X12.10 Y0.00 Z4.65
  - PID settings: M301 P22.20 I1.08 D114.00
  - Hysteresis (mm): M98 X0.00 Y0.00 Z0.00