Hi There,

I have been going nuts trying to diagnose an issue with a - C35 - QUICK SETUP BREAKOUT BOARD - I can get Mach 3 to work just fine without the breakout simply by wiring my three controllers (X,Y,Z) directly to the parallel port. but when i use them in conjunction with the breakout board i get BUBKIS! i have tried both ways jumpering SCHP to both the On and Off configurations and enabling it in Mach3 on pin 17. Either way i do not get signal to the controllers. in fact zilch from the controllers. when i use the controllers direct via parallel port the three axis "lock up" and are ready for input from Mach3, when i use the breakout they move freely, nothing seemed to be coming from the controllers.

i have supplied the breakout with +5V clean DC, with up to 4amps if needed. the board's "power" led lights as well as the "output status" led if SCHP is disabled or of enabled and signal is present on pin 17. I have replaced the RJ45's cables that connect the board to the controllers and rang them thru with a VOM so i have eliminated bad cabling.

Could it just be a bad board? where do i look next? is there some definitive test for a breakout board? what is the meaning of life? HELP!!!!

Thanks,
Jen

Could well be an issue with the BOB. I am not familiar with the CNC4PC stuff but I have read that often the optos can have issues on them. Whether yours has optos or not afraid I dont know but an email to Arturo may be the best way to go.
Hood

Thanks Hood, who is Arturo?

Arturo Duncan, the guy that makes the CNC4PC boards.
Hood

Have you run 5vdc to the EN terminal (enable) without it the output will not work.

(;-) TP

Thanks for the advice TP, I ran a jumper from EN to +5v, that was the first thing i did upon installation. i also checked that it was getting the correct voltage on the EN pin.

Hi Jen,

At the risk of stating the obvious, are you certain that you are making the correct connections between your C35 and your stepper drivers ?.
Have you also checked that the active high / active low signal condition between Mach and your drivers is correct ?.

Tweakie.

nb. Meaning of life and purpose of life are the same thing and can't be discussed here without upsetting the moderators 

Hi Tweakie,

Yes I verified the connections by "ringing thru" all eight pins on each of the three RJ-45 jumpers connecting the BOB to the controllers, even replaced all three of the jumpers to eliminate a "lossy" connection. they are "straight thru" CAT-6 cables as opposed to the ones that "cross over". Also i tried both methods of the active high and active low signal types from Mach-3. Because it works when i bypass the BOB i must assume that Mach-3 is doing it's job.

I ordered another BOB on Saturday, so by mid week should know if it is the BOB, unless i wind up with two bad boards from the same supplier.

I have only been playing with CNC for three or four weeks now, it is amazing how much knowledge i have been able to accumulate in this old brain in such a short time. the good part is i have been able to set up my router, have purchased the CAD software and am well into drafting the parts for my first CNC cut ukulele. That's right i am a luthier and inlay artist trying to bring my skill set into the 1990's.

what i would like to know is what the BOB expects in the way of input from the parallel port. is it just a nice square 5v "wave" for "step" and the same to change "dir"?

Perhaps i can use this as an excuse to buy myself a nice new O-Scope one of those digital recording ones. i have an old war surplus dual beam that world make a fine mooring for a small yacht. but it gets the job done.

one thing i did notice is that when i remove the 5v supply from the BOB and connect it to the parallel port the power led still lights on the BOB. I can only assume that it is usurping some power from the parallel port. Is this normal? the board does recognize when it is connected to the parallel port, because the "output status" led light goes hi when it is connected.

i remember an old shaggy dog joke regarding the meaning of life, it's punch line (after about ten minutes of rhetoric) was "Life is like a waterfall"

thanks everyone for your advise to this point, it is more than appreciated,
Jen

Hi Jen,

Thought you would have tested the wires continuity and connection points but worth a try.

what i would like to know is what the BOB expects in the way of input from the parallel port. is it just a nice square 5v "wave" for "step" and the same to change "dir"?

The direction signal is either high or low and remains in it’s set state until another command tells it to change (axis move in opposite direction). The step signal is a square wave pulse which Mach allows to be altered in terms of width and active high/low.
Most BoB's require a 5 Volt peak to peak signal here and some computers, especially laptops, only output around 3.3Volts and these do cause problems.
Most PC parallel ports are more than capable of sourcing 10 mA per pin so would light your BoB leds but it is risky to over do it and possibly damage the port.

Just a thought here but have you tried Config / Ports and Pins - check the ‘Sherline ½ Pulse Mode’ box ?  this alters the pulse width and may cause different results.

Lets hope it is the BoB and that your new one solves the problem.

Tweakie.

Thanks once again,

I will try your suggested fix, and scope out the signal on the "step" pins just to see what is going on when i get home from the saltmine. I'll let yall know how i make out.

Also thanks for the note on the power led, i was worried that applying current to the power terminal from the seperate power supply I had fitted to the BOB could somehow feed back to the computer and cause an issue. I found a really clean switched power supply capable of a continuous 5A's in a nice small steel case for less than twenty bucks. when I scoped the output it had very little ripple.

Jen