Machsupport Forum
Mach Discussion => General Mach Discussion => Topic started by: k.kuramochi on May 24, 2007, 11:18:31 PM
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I am trying to use machmill.
I am observing stp & dir pulses by an oscilloscope but I can't see any pulses.
please teach me why.
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You wont see pulses for direction changes but you should see a deflection from 0V to 5V and vice versa when you change direction back and forth. For the Step you should see pulses, the faster you move the axis the more pulses you should see, ie the frequency of them will increase with axis speed.
What voltage scale do you have your scope on? if your probe is a 1:1 then yyou should have your scope on 5V and if your probe is 10:1 it should e on 0.5v range. You will then just need to play around with the timebase to get it right, try the timebase at 0.1 and work from there.
Hood
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Oh another thing, make sure your scope is working, there should be a calibration poit on the front, when you put the probe on that and set the volts and timebase to the correct ranges you should see a nice square wave.
Hood
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Oh another thing, make sure your scope is working, there should be a calibration poit on the front, when you put the probe on that and set the volts and timebase to the correct ranges you should see a nice square wave.
Hood
There is no problem for using a scope.
Before the mach is started, step signal is 0V. After the mach is started, step siganal become 5V, but there is no change during joging. The DIR signal is always 0V in back jog, forward jog and during ta est G-code program is running.
Thank you for your reply.
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Try a different PC or a different Interface card. I went through three PC's till I found one with the right parallel interface.
Lemo
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k.kuramochi
Sorry for giving you the basics of a scope, just wasnt sure if thats what you were asking.
OK if you Jog the axis via keyboard do you see the on screen DROs moving?
Have a look in Ports and Pins and make sure you have the correct port address set for port 1.
Have a look in the motor outputs and make sure you have that port set for both step and direction.
If you have all the above does the scope go high or low when you check or uncheck the active Low setting on the motor outputs page?
Hood
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I have tried two kind of PCs. Those are Dynabook(Toshiba) and ASUS mother board(P5VDC-MX).
The status is same each.
Thanks for your reply.
k.kuramochi
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I use Port#1(0x378).
X Axis's step pin#=2, dir pin#=3.
When I check or uncheck the active Low setting on the motor outputs page, I can't watch any change of the step and the dir signals.
k.kuramochi
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can you post your xml , I might see something wrong
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Inside the Mach3 folder is a file called SpecialDriver double click it to run and it will install a different Port driver, I had to use it on one of the PC's I tried.
Graham.
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I installed SpecialDriver but after that jog operation doesn't work. DRO of position freezes.
Thanks for your reply.
k.kuramochi
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k.kuramochi
I just tried your xml that you sent and it works fine on the scope here. I did see that you had the velocity of each axis set very low which made it harder to see the pulses on my old scope but they were there. Also the direction on all three pins were changing from Hi to Lo as they should.
If you can try increasing the velocity of the motors and see if that helps you read the scope. If you still dont get any outputs then either you have a bad port or possibly a bad cable or a crossover cable.
Hood
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Ok, just double click OriginalDriver and it will be back to standard.
Graham.
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After Special Driver was installed, jogging operation doesn't work. DRO for axis position is freezed.
Thanks for your replay.
k.kuramochi