John,

I don't have the Android app that you'd like and I almost hesitate to suggest my solution. However, here goes!

I would use a 28pin 'Micromite' for this. I have several just built on (what I still call) Veroboard and they essentially just need a PIC32 MCU chip and two external components (a resistor and capacitor) to form a working system. They are very simple to hook up to just about any device and for instance I use £1.50 TV remotes to control mine using an IR connection. Very simple or (if you want) very complex LCD screen support is provided. I programme my own PICs but you can get them pre-programmed. They boot standalone once programmed via a serial lnk to a laptop.

Or you could of course use an Arduino or more traditional PIC controller.

So why a Micromite? Well because Micromite Basic (MMB) is just so nice to work with interactively. Just one line to use the IR control, just one line to 'PWM'control a servo or motor, simple serial comms (and many other comm. protocols) all embedded in the language.

Forget any prejudices about using "Basic" (I had them) this is a modern language (no line numbers) and is more than fast enough even on the 28pin MM. However, if you ever need speed, there is now a large range of devices that MMB runs on – faster PIC32s, ARM Cortex devices, R.Pi and PCs

But the best reason to use MMB is for ease. You can programme a Micromite interactively from your PC screen and debug it the same way. No compile, load, test, recompile etc cycle that is required of most micro programming systems – including Arduino. If someone has a quick solution, then of course use it. But if you find you need to cook your own, then the MM will get you there faster than any other solution for this kind of programme control. I know many here will disagree – and to them I'll just say, I've tried other solutions and MM is the one I much prefer.

It is also very well documented and has an active (and friendly user forum). Start here…

Micromite – Geoffs Projects

Pre-programmed Micromites, PCBs from a UK source here

Micromite in UK

That's it. If you try this I think you will be pleasantly surprised with what an elegant solution MMB is – even on a simple Veroboard with just a few components.

Regards,

IanT

Hi John,

I use an Android App called Grbl Controller to send Gcode to a 3-axis Eleksmaker Grbl controller over Bluetooth serial (based on an Arduino nano with added HC-05 or similar Bluetooth module). The motherboard and nano cost little more than £20. It works very well and the App is free. you can send Gcode files, or just use up/down left/right etc buttons on three axes. I think it came pre-flashed with Grbl, but anyway no editing required, except for maybe baud rate in the config.h file.

Andrew.

Edited By Andrew Entwistle on 12/05/2020 13:51:14

Edited By Andrew Entwistle on 12/05/2020 13:53:05

Grblgru

I have installed this & had it communicating with the latest Grbl version (v1.1) on an Arduino, though have not yet tried driving a machine with it (machine still not ready).

Also had Universal G Code Sender doing the same UGS website

Nigel B.

Have you seen these, John ? **LINK**

https://www.ebay.co.uk/itm/Offline-Hand-Controller-Manual-Control-for-GRBL-Control-Laser-Engraving-Machine/113002082998

… I keep wondering whether that might be a good option

MichaelG.

< deleted double post >

Edited By Michael Gilligan on 12/05/2020 21:48:27

Not quite answering your question but I started with GRBL on an Uno and ended up running Marlin firmware on a Mega 2560. If you run Marlin then you have the option of an LCD screen and a memory card on the controller itself as well as running off G code from an external 'sender'.

My own reason for running Marlin was software backlash compensation. GRBL also has a version that can do this but it won't fit on an Uno – you need a Mega 2560… the killer for me though was that moving to GRBL on a Mega means moving to completely different I/O pins and therefore not being able to use the CNC shield. I was able to set up Marlin to work with the CNC shield.

On the downside, Marlin's 'sweet spot' is 3d printing so it is a bit odd for CNC.

Regards, Andy