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GRBLDroid-USB

Official Description

Pilot your CNC machine using the GRBL firmware and this android app.
You need an OTG USB cable in order to connect your android device with arduino.
Uses *.gcode files ONLY (ex: TEST.gcode)
Please read the online documentation :
http://www.trustfm.net/software/mobile/GRBLDroid.php?page=Documentation

1) GRBLDroid-USB will work only with GRBL 0.9 versions

2) GRBLDroid-USB supports simple and advanced file mode.
I have followed the official instructions from here :
https://github.com/grbl/grbl/wiki/Interfacing-with-Grbl

The simple mode is as described here :
Streaming Protocol: Simple Send-Response [Recommended for Grbl v0.9+]

And the advanced mode is as described here :
Streaming Protocol: Character-Counting [Recommended with Reservations]

3) GRBLDroid-USB checks if the commands are 80 lines long (including the last enter char)

4) It is recommended to purchase a dedicated tablet for this job with a DC IN 5V jack.
With this jack you can always recharge the tablet and at the same time it will stay connected on your CNC machine via micro USB OTG cable.

5)GRBLDroid-USB works for :
FTDI FT232R UART
FTDI FT231X
Arduino
Teensyduino
CP210x UART Bridge
Prolific PL2303
Qinheng CH340
Official web page: http://www.trustfm.net/software/mobile/GRBLDroid.php
Online documentation: http://www.trustfm.net/software/mobile/GRBLDroid.php?page=Documentation