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Wal
07-01-2018, 06:17 AM
Hi folks,

I think I may have fried the bank of input pins on my BOB - it's one of the cheap Wantai boards that you get free when buying a set of drivers. I've found it to be a decent card and as such would like to replace it like for like.

Having said that, it's a long shot that there's one available, so hit me up with what you've got in the way of simple parallel port, 3-axis, 12v boards...

Wal.https://uploads.tapatalk-cdn.com/20180107/26c4323defd4498ee6a78c23c65b5951.jpg

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Desertboy
07-01-2018, 08:48 AM
I have this BOB
https://www.ebay.co.uk/itm/5-axis-CNC-Breakout-Board-with-optical-coupler-for-Stepper-Motor-Driver-MACH3/282673162800?hash=item41d0a22a30:g:bg4AAOSwQXZZzVW P

works fine and supports the same functions as the one you have, the USB is only to power the board with 5v.

UK seller so will be with you Tuesday, Wednesday do what I did and buy 2 as they are cheap as chips.

Clive S
07-01-2018, 09:54 AM
Having said that, it's a long shot that there's one available, so hit me up with what you've got in the way of simple parallel port, 3-axis, 12v boards... Are you sure it is 12V !! and not 5V

Wal
07-01-2018, 09:58 AM
Are you sure it is 12V !! and not 5VHehe. Yep, you're right, Clive..!

(It's my switches that are running off 12v.)



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john swift
07-01-2018, 02:14 PM
the BOB requires a 5V supply if you fit jumpers JN1 & JN2
or two 5V DC supplies if jumpers JN1 & JN2 are not fitted

23551

the circuit diagram is based on photos taken from the net !!

John

PS
I assume the limit switches have NPN open collector outputs

with just the 5V power connected to the BOB you should have close to 5V
between the opto-isolator IC pins 3 & 4

when you connect the opto-isolator pin2 to the input ground with a wire link the voltage across pins 3 & 4 should drop to close to zero volts (0 to 0.7v)

it should be easy to change and damaged "817" opto-isolators

PPS

simple tester for similar BOB inputs

23552

TX14175 circuit
23553

Wal
07-01-2018, 05:43 PM
Cheers guys.

Panic over for now - turns out it was my brain cells that were fried and not the input pins. The switch was behaving differently to how I expected it to - rather than take a closer look at what the switch was doing, I began a campaign of button mashing which lasted well into the night - not a great idea after a full day of assembling the bugger..!

A clearer head this morning, a quick chat with Clive and a better look at what my switches were up to yielded better results..! (Oh, and restoring my back up .ini)

Should have it up and running in the next few days.

Wal.

john swift
08-01-2018, 10:32 AM
no damage done and now working
a good result

if you go on too long without a break its too easy to make the wrong decision and dig your self into a deeper hole

I know I have done it my self once or twice

John

Clive S
08-01-2018, 11:38 AM
I know I have done it my self once or twice
Only once or twice, I must have done hundreds of times:beer:

john swift
08-01-2018, 12:06 PM
Hi Clive

that was once or twice that could not be fixed before management noticed and started to ask questions !!!!

the others no body new about are just part of the iterative process

John