Need Help!- How do you add external control pots on Mach3

[neilw20]

I am sure it can be done.
Has anyone made external speed and feed over-ride controls using potentiometers?

[Al_The_Man]

Not sure if there is anything out there already, but it may be better to look at the common commercial O/R method of using a Binary switch, 4 bits give you 16 steps/switch.
Al.

[neilw20]

I will design a method. Just thought there maybe a way it is typically done already. No point reinventing the wheel, so to speak.

Needs to be at least 8 bits to be fine enough to be practical.
I suppose you could up/down button, but that is not nice, and the latency would make it awful to use.
An 8 bit switch if it must be digital.
Can always make an 8 bit output A/D converter, but it will need gray code output so every step is different. Then how do you feed that into Mach3?
That is a lot of bits for 2 pots, using a parallel port.
USB, maybe, but will latency be an issue?
I suppose an MPG type input could be made to work.

[ger21]

The easiest way is probably with a Pokeys.
PoLabs - Affordable PC USB oscilloscopes, logic analyzers and USB interfaces

They have analog inputs and apparently work well. Never used one, though.

[Al_The_Man]

I see there is a plugin for Contec PIO boards, I am surprised that by now no one has developed a PC Based PLC for Mach using these cards.
All the preferable operator hard wired functions such as feed hold and feed overide, spindle O/R etc could be done digitally this way without messing with analogue inputs etc.
A resolution of 255 is hardly necessary for most overides.
Al.

[neilw20]

The PoLabs idea looks good with the plugin, and 10 bit is more than adequate!

Any other ideas out there? Now we are getting somewhere.

[ger21]

Looks like you can use a ModIO as well.
Touch Screen and panel controls using ModIO - MachCustomizeWiki


MC-01 ModIO Controller [MC-01] - US$98.00 : Homann Designs!, The preferred CNC Component Supplier

[jrobson]

USB Modbus Interface - Field of Cows