Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: CNCdn on March 09, 2010, 12:26:07 AM

Title: Motor outputs????
Post by: CNCdn on March 09, 2010, 12:26:07 AM
REALLY new to CNC in general and Mach3 in particular so bare with me a moment.
In the diagnostics screen, I am not seeing any "LED's" in the 'port pins current state' whether at rest or while jogging.
X,Y and Z are enabled in the 'ports and pins' cofig file.
Obviously, steppers aren't moving either (hobby cnc board) but are locked up when powered.
I've read through the manual but perhaps I've missed something.
Any help appreciated.
Alex in Texas
Title: Re: Motor outputs????
Post by: Dan13 on March 09, 2010, 01:18:17 AM
Hi Alex,

The LEDs on the diagnostics screen don't show the motor pins activity. First make sure you defined the right pins and right port (port 1) in the ports and pins. Also make sure the parallel port address is defined correctly, as described in the manual (I think it's there...)

Daniel
Title: Re: Motor outputs????
Post by: CNCdn on March 09, 2010, 10:49:40 AM
Daniel.
Certainly, I am confident that the port is correct but not too sure about the pins themselves.
Since I do not have a schematic of the driver board, I'm not sure how to tell.
Do you know if I can use a multimeter to do any testing?
Alex
Title: Re: Motor outputs????
Post by: Dan13 on March 09, 2010, 11:13:05 AM
You can define a spindle relay on one of the pins of the parallel port and then use a multimeter to measure the voltage on that pin and see if it actually changes when you command Mach to turn the spindle ON and OFF. This is one easy way to check your parallel port actually works.

Daniel
Title: Re: Motor outputs????
Post by: Hood on March 09, 2010, 11:14:42 AM
You can easily check Dir pins with a voltmeter, just jog one way and then the other and the Dir pin should change between 0v and 5v or vice versa.
The Step pins can also be looked at whilst jogging but you will only see a small change in voltage, if set active High you will see the volts go from zero to possibly a few hundred mV, if set active Low you may see the 5v drop a bit when jogging but really a scope is needed to see exactly whats happening on the step pins..
Hood

Daniels beat me to it with a reply :D
Title: Re: Motor outputs????
Post by: CNCdn on March 09, 2010, 11:47:11 AM
Great idea Danial. I'll try that right away.
Also great info from you, Hood, but the best is an excuse to buy a scope. I had a (really) old Heathkit before moving to Texas. Bought a newer one but my son needed it "for a while" while doing a project at school (electronics engineering). That was two years ago. I've stopped asking!!
Thanks to both.
Alex