Updating the Firmware

Overview

This is a list of steps to follow when updating the Grbl firmware.
We’re currently storing the firmware and settings here:
https://github.com/HACManchester/Tools.OxCNC/tree/master/Firmware

Backup Settings / Firmware

Backup Settings

The first thing we need to do is backup the settings from the Grbl firmware / Arduino

• Hook up the arduino board directly to a laptop using the USB cable that runs into the Rpi
• Open putty and connect to the Grbl / Arduino Uno
• http://www.chiark.greenend.org.uk/~sgtatham/putty/download.html
• Type $$ followed by a carriage return
• Copy and paste the output into a text file

Backup Firmware

If you want to backup the existing firmware:

Under windows (check the com port number)

cd C:\Program Files (x86)\Arduino\hardware\tools\avr\bin
avrdude -C "C:\Program Files (x86)\Arduino\hardware\tools\avr\etc\avrdude.conf" -p m328p -P com4 -c arduino -b 115200 -F -U flash:r:C:\Apps\flash.hex:i
avrdude -C "C:\Program Files (x86)\Arduino\hardware\tools\avr\etc\avrdude.conf" -p m328p -P com4 -c arduino -b 115200 -F -U eeprom:r:C:\Apps\eeprom.hex:i
avrdude -C "C:\Program Files (x86)\Arduino\hardware\tools\avr\etc\avrdude.conf" -p m328p -P com4 -c arduino -b 115200 -F -U efuse:r:C:\Apps\efuse.hex:i
avrdude -C "C:\Program Files (x86)\Arduino\hardware\tools\avr\etc\avrdude.conf" -p m328p -P com4 -c arduino -b 115200 -F -U lfuse:r:C:\Apps\lfuse.hex:i
avrdude -C "C:\Program Files (x86)\Arduino\hardware\tools\avr\etc\avrdude.conf" -p m328p -P com4 -c arduino -b 115200 -F -U hfuse:r:C:\Apps\hfuse.hex:i

Under Linux it will be something like

avrdude -p m328p -P /dev/tty.usbserial- -c arduino -b 38400 -F -U flash:r:backup1.hex:i

Flash new Firmware

Download Files

Next we need to grab the latest firmware version

• https://github.com/gnea/grbl
• Version 1.1f (2017-08-01) seems to be the latest at the time of writing
• The board in use is a arduino Uno with a 328p chipset so this should match the downloaded binary

Next download XLoader

• http://russemotto.com/xloader/

Flash Firmware

Next to flash the new Hex file to the Arduino

• Reset the Controller board
• Open XLoader
• Select the correct COM Port
• Make sure Arduino UNO is selected for the device
• Browse to the new hex file
• Click Upload
• Wait for the upload to complete

Restore custom settings

As a final step we need to restore any custom settings that were originally applied

• Connect via putty (with the latest firmware this is now at a speed of 115200)
• Use $$ to list all settings
• Add in any differences needed to the settings
  This includes settings such as how many revolutions per travel of mm / soft limits etc