DIY 3020 CNC I/O Board

[EddyCurrent]

Les, You say you have a version of this that works well, so by making the changes to it's own supply and using opto-isolation surely this one will work fine too ?
Using pull up resistors is good, that last thing you want is an input that's floating about and susceptible to induced voltages so it needs to be tied to one leg or the other.
This is only one board so are you going to show how it fits into the complete system ?
If you notice, things like stepper motors, limit switches, spindle to some extent, are all wired in more or less the same way so it's the emergency stop circuit that interests me most.
Correct me if I'm wrong but you are using Mach3 on this job ? are you going to use the charge pump feature ?

[Pointy]

Les, Just explain what happens when you hit the emergency stop button, I don't mean the flip flop changing state, LED's and input to OK1A, I mean after that.
If you notice, things like stepper motors, limit switches, spindle to some extent, are all wired in more or less the same way so it's the emergency stop circuit that interests me.
Correct me if I'm wrong but you are using Mach3 on this job ?

Yes I am using Mach3, the Estop switch just pulls pin 10 low. That's all it did on the original board/switch. I just added the flip flop. Mach3 detects the low and stops everything, there is no hardware emergency stop if that's what you mean.

Regards,

Les

[EddyCurrent]

I changed my post but you have the original text, I thought afterwards I was jumping the gun when you were really asking about this board only.
It's a matter of scale probably, it's a 3020 after all so is there going to be a real emergency ? I don't know, what do you think ?

[Pointy]

Les, You say you have a version of this that works well, so by making the changes to it's own supply and using opto-isolation surely this one will work fine too ?

Ah, but working and being safe are two separate things!

It's a matter of scale probably, it's a 3020 after all so is there going to be a real emergency ? I don't know, what do you think?

The EStop just being software is fine to be honest, I can always change it in the future if needed.

I am going to order some parts and test it out on the breadboard over the next couple of days. I will let you know how it goes.

Regards,

Les