Machsupport Forum
Mach Discussion => General Mach Discussion => Topic started by: wadeanres on September 04, 2016, 11:57:56 PM
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Hi group, had a quick clarification. I'm trying to set up my Mini CNC and was checking the voltage on my 25 pin port in back of my computer. According to what I have read so far I should be able to read apx 5 volts when pressing the arrow keys. I just tested my top row 1-13 right to left and all are reading 5+ volts without touching any arrows. Any ideas?
A quick addition, my bottom row 14-25 left to right is reading pin 14-22 is reading 00 and pins 23-25 read 5+ volts with no arrows pressed.
Thanks Wayne
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Welcome to the forum.
Something is not quite right there as pins 18 to 25 are defined as signal GND so I think they should all be at the same potential (they are all at the same potential on my PC but perhaps some PC's are different ?).
Please see section 4 of the Mach3 manual http://www.machsupport.com/help-learning/product-manuals/
Tweakie.
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Thanks for your reply, I have read the manualseveral times and that is why I think something is not right but not sure what. The download went well my test run with the Road Runner
G-Code went well. When I test my arrow keys my axis move in the program. However I'm not getting movement on my stepper motors. So I tested my port pins in the back of my computer. As I said my entire top row 1-13 are hot with 5V my bottom pins are 25-16 are 00 and pins 17-14 are 5V (I had the bottom row info reversed in my first post.)
So see if I understood, pins 1-9 are output, pins 2-7 are XYZ outputs these should only have voltage when the corresponding arrows are pressed. Pins 10-13 are input, The input should read 00 since there are no signals being sent from the cnc board back to the computer. My 10 pin is my E-Stop. Pins 25-18 are common and should read 00. 17-16 are output 15 input and 14 output. Am I correct ??
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You are correct regarding which pins are inputs, outputs and GND.
However, I don't think that all unconnected input and output pins will automatically be at 0 volts.
Tweakie.
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From what I have read and viewed on the tutorials there should be a 00-5v difference in a pin when the + and - arrows are pressed. for example pin 2 and 3 are the X Axis pins. when pressing the +X arrow testing pin 2 you should read 5v. When you push the -X arrow pin 2 should now read 00. I have a constant 5V.
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If you have set up Mach3 so that pin 2 is the X axis Direction pin and you have set the Step port to 1 & Direction port to 1 then yes the pin voltage should toggle between TTL high and TTL low (measured between pin 2 and pin 25) when pressing the left and right arrow keys - provided; the X axis direction pin is enabled, Jog on/off is enabled, the X axis DRO changes value (increase/decrease) and that the correct address has been entered for Port #1 also that it has been enabled.
Tweakie.
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Hi wadeanres,
are you using a breakout board?
Directly probing D connectors is a good way of making problems rather than solving
them. Often the smallest of slips and two adjacent pins are shorted together any very
tender TTL circuits wont survive.
The breakout boards I use have an LED for each I/O and make diagnosing faults SO
much easier. Not all BOB's have them but most do. Worth every cent!
Craig
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I'm isolating my pins by inserting a paper clip into the individual pin holes on the Db25port in the back of my comp. My card is fine my drivers checkout. I have a BOB and power source isolated inside a metal CNC control box. Since I'm not even hooked up to the BOB none of that is an issue. I can't get any reading off any pins . I have 5v on pins 1-13 but can not get a change on any of them when testing my X Dir Pin. I've tried setting each pin to my X Dir Pin setting. None have given me any change in voltage. I understand my step pins won't give me any readings because I'm not using an oscilloscope but my Dir pins should have a voltage reading and show a 00v reading when pressing the - arrow to that axis. I'm working with Mach support to see what I can try.
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Do you have Mach3 running? Just a thought.
If the parallel port driver is not running you will not
get any expected response.
olf20 / Bob
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I've tested my drivers, drivers are good, my port settings are set to port 2 and my I/O is 800. Port 1 has been disabled and port 2 is enabled. My Mach3 program is fine, pins 1-13 have 5v so I'm getting current out of my Db25 port in the back of my comp.
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Hi wadenres,
have you run the driver test program? It is not an ironclad test that everything is
working but usually gives pretty good insight.
Also go to your device manager and confirm that the port numbering is correct.
Is there a reason you're using port 2?
On my PC port 1 is built in with what seems to be a widely used standard port address
and usually identical to the default port 1 address in Mach3. It was the first port I used
when starting out and had no issues with getting it to work.
Craig
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Mach is running fine, Port 2 is my Db25 card and has no driver issues and is suppoted by EPP mode. Think I might scrap my comp and get a fresh comp running XP with a Db25 port built into the mother board which would give me LPT 1 for my default port.
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UpDate,
The Machine is up and running. Found a youtube video with the correct settings for my machine. The one page set up that came with the machine was close but no ringer. Scrapped my modified PC, picked up an XP 32 Bit PC with a parallel port entered the new settings and Bingo. Thanks for all the input, everyone has been helpful.
Wayne