themainframe / power-feed

Arduino single-axis milling machine power feed controller

power-feed

Single-axis Arduino-based milling machine power feed controller.

Ported from Chris Mower's original millcode project (https://github.com/kintekobo/millcode). Pin-compatible with the original.

Features

• Rapid and Precision feedrates.
• Iconographic display of current mode.
• Control via physical buttons or over the serial port/USB:
  • stop - All-stop
  • fl - Fast-left movement
  • sl - Slow/Precision-left movement
  • sr - Slow/Precision-right movement
  • fr - Fast-right movement
  • 1000 - Set the precision feedrate to 1000 micrometers per second.
• Hardware timer-based pulse generation with endstop and safe-stop detection before pulse generation.
• Endstop backoff (see ALLOW_BACK_AWAY_FROM_ENDSTOP in defs.h) - optionally allow moving in the opposite direction after triggering the endstop.

Hardware

Written to work the original M542T stepper motor driver and I2C (PCF8574 I2C IO expander + Hitachi LCD controller) display backpack.

For the rotary encoder, two 100nF capacitors between the quadrature outputs and ground are essential.

Libraries

You'll need the LiquidCrystal_I2C library to use the same display used in the original project, however it would be easy on one of the higher pin-count Arduinos to switch to the traditional Hitachi parallel LCD controller. There aren't enough pins for this on the Uno/mega328p though.

No other libraries are used.