Hello Guest it is August 18, 2019, 08:17:10 PM

Author Topic: Fried 2nd Computer (Newbie)  (Read 16584 times)

0 Members and 1 Guest are viewing this topic.

Offline da21

*
  •  87 87
    • View Profile
    • M-Machine
Re: Fried 2nd Computer (Newbie)
« Reply #20 on: June 06, 2008, 05:12:55 PM »
Hi Travis
yes wiring the bob to the 7812 will be fine

try firing it up without the pc connected first , if you want to check out the drives
by momentary connecting the step pin to the 0v rail , you should hear and see the approprate motor take a step
then by repeated touching you should see it rotate ,

dont worry over which way the motor goes at this stage , if all is well with all 3 motors then go ahead and connect the pc
but not untill

Dave
 
Re: Fried 2nd Computer (Newbie)
« Reply #21 on: June 06, 2008, 05:32:29 PM »
Hello Dave

I'm not sure what the 0volt rail is ? Is it ground?

Thanks

Travis

Offline Hood

*
  •  25,849 25,849
  • Carnoustie, Scotland
    • View Profile
Re: Fried 2nd Computer (Newbie)
« Reply #22 on: June 06, 2008, 07:49:58 PM »
0V is the connection of your power supply that is not the positive, it is what people often call  ground but its not really ground LOL

Hood
Re: Fried 2nd Computer (Newbie)
« Reply #23 on: June 06, 2008, 09:06:37 PM »
Thanks Hood & Dave

Ok this is what I have. When I tried to power up Probotix Bob with 12volt Lm7812 with nothing else connected the LED came on I checked voltage and had +5 volts on all the pins that are suppose to have 5 volts. When I connected board to this other computer that has a bus speed of 800Mhz and CPU speed of 1.9 Ghz Mach3 had lines running thru the screen horizontal lines and LED on bob never came on. I then turned off power immediately didn't look good. I guess i'm still freaked out about frying my other two computers. The breakout boards are not the problem can't be what are the odds of three different breakout boards being bad. Could it be my paraell port cables. I have two one from radio shack and the other is Belkin. Same results.  I must have a short somewhere, but where?
None of this is making sense. I'm totally at a loss. Anyone know what might be my problem.

Thanks

Travis


Offline Chip

*
  • *
  •  2,056 2,056
  • Gainesville Florida USA
    • View Profile
Re: Fried 2nd Computer (Newbie)
« Reply #24 on: June 07, 2008, 01:28:38 AM »
Hi, Travis

Check to see if you have 5 volts on any of these pins, 18 - 25, With your cable/BOB not connected to your computer.

Thy should all be Gnd.- 0 - Return pins and should be 0 volts, Check the connector metal housing also.

Hood, What is "Gnd.- Zero" ?, Answer:  eB oT ecalP daB A

Chip

Offline jimpinder

*
  •  1,233 1,233
  • Wakefield, West Yorks, UK
    • View Profile
Re: Fried 2nd Computer (Newbie)
« Reply #25 on: June 07, 2008, 03:16:12 AM »
THIS IS GETTING TOTALLY *********

Have you got a wiring diagram for all this, or are you making it up as you go along. You keep quoting chip numbers to us when talking voltages - yes, alright, these are regulator chips - but why so many.

Have you designed this in three easy stages as I suggested, or are you still trying to just fasten it on one board and connect all the wires together.

You must get some system. You must have a diagram for each stage of the system - and you must stick to the diagram.

Try Drawing a diagram of the Bob board, and the power supplies you have connected to it first. Post that on this post and we will look at it and give you an opinion.

No, it is doubtful that you have bought 3 faulty boards - but you never keep the same board long enough to learn where your mistakes are.

I put in a previous post - there are three parts to the system Computer, Bob board, Driver boards. Lets do one thing at once !!! ???



Not me driving the engine - I'm better looking.
Re: Fried 2nd Computer (Newbie)
« Reply #26 on: June 07, 2008, 02:54:43 PM »
Thanks Chip

I checked both parallel port cables and I have 5volts on the outer shell of the d connection no ground on pin 18-25 and also noticed on the cables in small print IEEE 1284 high speed. I ordered two cables from Probotix hopefully this will solve the problem. i found an old Iomega LPT cable that is female to male and it has a totally different number and description altogether. Can someone tell me the cable part number I am suppose to use?

Working on drawing and yes I did the wiring in my head I didn't have a diagram. Maybe next time I will take more time.

Thanks

Travis

Offline Chip

*
  • *
  •  2,056 2,056
  • Gainesville Florida USA
    • View Profile
Re: Fried 2nd Computer (Newbie)
« Reply #27 on: June 07, 2008, 03:36:13 PM »
Hi, Travis

You Should Not have 5 volts on the Outer Shell, It's a Gnd/Shield, Pin's 18 through 25 are also Gnd/Returns pin's.

On the Printer Port connector on your Computer the outer shell and pin's 18 through 25 all come together as Ground's.

That's why your BOB board is Shorting Out Everything.

Pin's 1 through 9, 14, 16, 17, are output's used by Mach to send 0 volts or 5 volts to your BOB/motors/turn on and off things.

Pin's 10 through 13 & 15, are input's used by Mach to see, 0 volts or 5 volts from your BOB/system/limits, E-stop switches, speed pulses and such.

Thanks, Chip

Offline da21

*
  •  87 87
    • View Profile
    • M-Machine
Re: Fried 2nd Computer (Newbie)
« Reply #28 on: June 07, 2008, 05:25:59 PM »
your making an easy job into a long term nightmare take one step at a time as jim says
make a wiring diagram ! ,

check each part seperately , power supply first because if thats wrong everything else will be
check your break out board , then check out your driver board

give us a diagram and we can have this sorted in one go
 
Re: Fried 2nd Computer (Newbie)
« Reply #29 on: June 07, 2008, 11:38:09 PM »
Here is diagram I drew with MS Paint.  Not very handy with the mouse trying to draw. I don't have a scanner so I can't upload my sketch.

« Last Edit: June 20, 2008, 02:10:56 AM by trev36 »