Pluto-P Friendly BOB

[epineh]

I am at the stage where I want to create a Break Out Board to plug my Pluto-P board into, my thinking is to actually make 3 boards, one input board for things like E-stops, limits and homing switch's, one board for outputs spindle, vacuum clamp etc, and one board for the encoder inputs and PWM signals.

I am thinking of the BOB's to be straight thru, and will put opto's on the add-on boards - H-bridges , Input and Output.

I plan to mount all of this together, spaced with plastic stand off's to make termination easier and neater.

The reason I want three seperate boards is to take one ribbon cable from each header of the Pluto directly to the respective board, is this reasonable thinking or am I being stupid ? Any suggestions for improvement?

I can fabricate PCB's easily at home so I can try a few different methods.

Cheers.

Russell.

[acondit]

Russell,

How about creating a BOB with a set of holes that match the Pluto-P and mounting header pins on Pluto-P and header sockets on the BOB (or vice-versa) so that your Pluto mounts like a daughter board to the BOB?

Then you could just come off of the BOB with whatever outputs or inputs were appropriate. You could mount a 26 pin idc double row pin connector to take a short 26pin to DB25 ribbon cable from the BOB to the Pluto and a DB25 connector into the BOB to be connected to the Pluto through your opto-isolators.

Is this all clear as mud?

Alan

[epineh]

Great idea Alan, I take it you mean bring the parallel cable straight into the BOB, through opto's, then up to the pluto via a DB25 ribbon, with the Pluto plugging in to the BOB, that would be pretty neat.

I have read something about not using opto's for the parallel port side of things with the bi-directional mode of parallel port that the the Pluto uses, but that could easily be left out, and I can still use the DB25 on the Pluto for the cable input.

I do like the idea of plugging the Pluto straight onto the BOB and think I will run with that, now I have to work out the measurements so the two align, can I use a hammer to "adjust" for any errors ? ...lol

Thanks again ,

Russell.

[acondit]

Russell,

I am interested in how it turns out. I have a few small servo motors and have been thinking about getting a Pluto-P myself.

Have you already got your design for the H-Bridge?

Alan

[epineh]

For the H-bridge I am being a bit lazy as I have a friend who is designing one for his machines, which are more commercially based routers. I am going to "help" him by using my machine as the guinea pig. I will get his design and build it at home.

I was going to use Samco's boards as they seem quite good, but I think the components he used are too hard to locate here in Australia (same old story).

He has posted them and links on my router build log :

http://www.cnczone.com/forums/showthread.php?t=22101

Look at the end of the log, he has listed them there.

Lol I just checked and you have already posted there so I guess you know about his boards

Cheers.

Russell.

[acondit]

Yes, I have seen Sam's H-bridge. My problem is that I just don't know enough about H-bridges to evaluate what is good and what is not. I hate to spend a bunch of money and be dissatisfied. I have downloaded a few pdfs on H-bridges, so I guess I need to actually read them now. I guess for a start I'll create a BOM and see where I can find the parts and what they cost.

Alan