Mach3/DB25/BoB issue....?

[gearsoup]

This is probably a "no-brainer", but I figured I'd toss it out here and see what I got.

I bought a "new computer HP Compaq DC7600 Desktop PC - Intel Pentium 4 3GHz, 2GB DDR2, 40GB HDD, Combo, Windows XP Pro at TigerDirect.com for my CNC router that I built 9 years ago.

It was running on some very old dinosaur running Windos98 with Master5 software. Yup. Master5. The CNC and PC have been in storage for several years now. I've gotten the urge to seriously start playing with it more.

Anyways, I took the opportunity to upgrade to Mach3 (demo version for now). I went to the Config dialog in Mach and confirmed that the printer address matched what was in the Resource window of the Printer Port dialog (in Window Hardware manager). The resource lists it as 0378-037F. Mach 3 keeps reverting back to 0x378. I assume this is correct?

I configured all 6 pins. There is one step and one direction pin for each motor. I do not have any limit switches or E-Stop switches setup yet. I will get to those later.

My breakout board is a simple PCB, no opto-isolators or anything. I am using pins 2,3,4,5,6,7. X,Y,Z respectively.

So, pins are configured, I've set the steps per inch to 10,000, since that I what I ran on Master5. I press the arrow key to job the machine, and .....nothing happens. It does not jerk, hum, or anything. It just sits there. Yes, there is power to the motors.

I borrowed a rather nice multi-meter from a co-worker, sad part is, I have very little clue where to start and what to look for (also, I've only used a multimeter a couple times in my life, and not for anything much really)

At any rate, I grounded out one lead and inserted the probe tip into each pin of my printer port and got these readings: Pins 1-4 are at 4.51 volts and .25 amps. Pins 5-12 are at 3.40 volts and 0 to .01 amps. Pin 13 is 4.51 and .026 amps. Pins 14-21 are 0 and 0. Pin 22 is .01 and 0. Pins 23-25 are 4.51v and .26A.
None of these values change when I depress a key to "jog" the machine. If I unplug and reconnect the printer cable, my motor will jerk one or two steps it appears/sounds.

If I am in Hardware manager and I uninstall the printer port, the 4.5 volts goes up to 4.85. When i click on "Scan for hardware changes" it drops back down to 4.51volt.

So, I am lost as to where to start and what to do. Any ideas on how to help me out? I am an almost total electrical noob. But, I'm able to comprehend ideas and whatnot...

[Al_The_Man]

Originally Posted by gearsoup At any rate, I grounded out one lead and inserted the probe tip into each pin of my printer port and got these readings: Pins 1-4 are at 4.51 volts and .25 amps. Pins 5-12 are at 3.40 volts and 0 to .01 amps. Pin 13 is 4.51 and .026 amps. Pins 14-21 are 0 and 0. Pin 22 is .01 and 0. Pins 23-25 are 4.51v and .26A. None of these values change when I depress a key to "jog" the machine. If I unplug and reconnect the printer cable, my motor will jerk one or two steps it appears/sounds. ...

No1/ Not a good idea to poke the leads in the PP port to common when using the meter on the current (amps) range. It is effectively a short between probes.
Al.

[gearsoup]

oops.
Also, after reading a bit. I think I numbered the pins wrong. I was going from left to right (looking at the back of the PC) Mach3 documentation shows that top right is Pin 1. So, I guess that changes things a bit.

[doorknob]

One of the easiest checks to perform with a multimeter is to see if the direction pin(s) show a voltage change when you change direction. Did you try jogging in both directions or only one direction, of one axis or all axes?

If you set your multimeter to measure volts, and you put the red probe on the direction pin for one of the axes, and the black probe on ground, and then jog that axis first in one direction and then in another direction, then you should see a logic "high" voltage in one direction (perhaps in the range of 3 to 5 volts) and a logic "low" voltage (near 0) in the other direction.

If you can establish that the direction signal is showing up on the expected pins, then the next thing to examine is whether or not your driver input can handle signals in the approximate range of 3 volts (some can, some can't). There is also a question of whether your PC's parallel port card can source or sink the right amount of current that your driver inputs require.

[gearsoup]

Well, for starters, I had the DB25 cable unplugged and I was just probing the printer port of the PC itself (that sounds dirty). No change was shown when I jogged in either direction on any axis. For ground, I was just attached to the PC case.

Not sure if this helps or anything, but I am using Gecko's. Not sure what exact line they are, but it would have been whatever was popular 9 years ago.

[doorknob]

In the Mach3 "ports and pins" configuration page, is the port set to 1?

Unless and until you can verify that the parallel port direction pins are responding to axis jog direction changes, I doubt that you will be able to drive the motors, since it is not certain that Mach3 is even talking to your port.

[gearsoup]

Yes, port is set to 1. I left the port address set to 0x378, as it appears that is the hexadecimal value for the onelisted in system resources.

I fear that you are right about it not even talking to my port. For instance, on the Diagnostics page (Alt-7) the readout: Port 1 pins current state. I assume those would be lit up as I jog the machine? They do not light up.

[gearsoup]

Is there a way to determine if the port is faulty?

[gearsoup]

It lives! woot!
I tried a few things, then I went into the BIOS and changed the LPT port from EEP/ECP to Bi-directional. wadda ya know. all good now!