Help Mach3

[dazp1976]

Hi
I now have a new lead and as before the Y axis only moves in one direction? If I chane position on bob then it is OK.
I have spent alot of money on this rebuild and time but dont seem to be getting any were with it. the limit switches only work intermitantly??

Mike

Could be the parallel port on the pc has gone then.
I would get a voltmeter onto the bob.
Put the +ve end on pc5v, put the -ve end on the dir pin.
Then toggle active low/high you should see it alternate between 5v (ish) and 0v (I/O for cw or ccw, that's how it works).
If you see no change, then the signal on that pin isn't working. So is either bob or port.


Ideally. The best way to test a pport is: you want to get a screw terminal board for your Parallel cable so you can test pport signal directly. Plug one end of cable into port/ other end into screw terminal board header.
(If your hands are steady you may be able to just do this by touching the pins on the pport itself but: don't slip!.)
Put the +ve probe end onto the output pin you want to test, put -ve end onto any GND pin 18-25.
Set a flood coolant relay to that output number. Now when you turn coolant on/off you should see voltage changes on the pin you set. If port isn't working you will see no change.

Then you should know where your at with it and go from there.