[matth]

I could see that working, but I think you will need to isolate the line's with a diode like they do on the DMM BOB? This way one alarm can't feedback into a different drive when it goes high?

It appears they are using the alarm lines to turn on a FET that basically pulls the e - stop to ground. If you did it like this, you wouldn't even need another input, however it might be easier (avoid using the FET).

You are correct, looking at the drive spec they have no opto isolation so I can't just tie them together. The diode method could be used or just use a 4 input OR gate.

[jevs]

Apparently CNC4PC says their C32 breakout board works great with the DYN3 drives and to use this connector:
CNC4PC

However, I had to reply back that I plan to use the DYN2 drives. Waiting for a reply on that.

[matth]

N.B. just been looking at hooking up my BOB to the first Dyn2 drive and I can't do it because the Dyn2 drives want a positive switched high pulse rather than the more usual switched low / common output of most BOB's (e.g. a permanent 5v to the + side of an internal opto isolator and then switching the negative side to ground).
I've been looking at the AKZ250 USB control boards but they also switch low so it might be necessary to add additional external opto isolators to reverse the switching.

[jevs]

N.B. just been looking at hooking up my BOB to the first Dyn2 drive and I can't do it because the Dyn2 drives want a positive switched high pulse rather than the more usual switched low / common output of most BOB's (e.g. a permanent 5v to the + side of an internal opto isolator and then switching the negative side to ground).
I've been looking at the AKZ250 USB control boards but they also switch low so it might be necessary to add additional external opto isolators to reverse the switching.

look at the connector I posted above from CNC4PC. I have been told this should work, but you would have to connect a pigtail to the db25 or modify the board (remove db25 and add wires). Basically you need that circuitry (whatever is there i cannot tell for sure). Of course I don't know if your Bob will work with that, but the c32 I am told should.

[matth]

It looks like all the CNC4PC board is, is a board with the correct connectors (for the Dyn3) and a couple of opto isolator chips for inverting the signal.

I probably make up a tiny PCB on vero board with a Molex right angle header on the side that can be on the end of the cable that connects back to the break out board. This PCB would only need a single opto chip (PC817) and a single resistor. The header would then plug straight into the Dyn2 drive.
Give me a week or so and I'll make one up and post up a picture.

[matth]

It looks like all the CNC4PC board is, is a board with the correct connectors (for the Dyn3) and a couple of opto isolator chips for inverting the signal.

I probably make up a tiny PCB on vero board with a Molex right angle header on the side that can be on the end of the cable that connects back to the break out board. This PCB would only need a single opto chip (PC817) and a single resistor. The header would then plug straight into the Dyn2 drive.
Give me a week or so and I'll make one up and post up a picture.

I tell a lie, it would need a opto isolator for the step and another for the direction and possible one for the enable as well.

[jevs]

Might be easier to buy one of those boards and mod it with different connectors or a at least see exactly how it is made.
I also heard they might be coming out with a new DYN2....have not confirmed with DMM.

[matth]

Might be easier to buy one of those boards and mod it with different connectors or a at least see exactly how it is made.
I also heard they might be coming out with a new DYN2....have not confirmed with DMM.

Not really.