Marlin 3D Printer Firmware Copyright (c) 2019 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
Based on Sprinter and grbl. Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with this program. If not, see http://www.gnu.org/licenses/. Gen3 Monolithic Electronics pin assignments Rev B 26 DEC 2016
added pointer to a current Arduino IDE extension A useable Arduino IDE extension (board manager) can be found at https://github.com/Lauszus/Sanguino
This extension has been tested on Arduino 1.6.12 & 1.8.0
Here's the JSON path: https://raw.githubusercontent.com/Lauszus/Sanguino/master/package_lauszus_sanguino_index.json
When installing select 1.0.2
Installation instructions can be found at https://learn.sparkfun.com/pages/CustomBoardsArduino Just use the above JSON URL instead of Sparkfun's JSON.
Once installed select the Sanguino board and then select the CPU.
1.8.16 
