Hello Guest it is March 28, 2024, 06:12:25 PM

Author Topic: Help with input signals please  (Read 3491 times)

0 Members and 1 Guest are viewing this topic.

Help with input signals please
« on: July 09, 2014, 03:05:19 AM »
Hi, I have set up a simple X Y  table to life test some joysticks, but I can't get the software to recognise the inputs from the switches. I have checked the switches with a voltmeter and they seem to be working fine.

I have two limits switches wired in parallel and a home switch on each axis. I set the pin to 10 and the port to 1, tick active Low but Mach3 won't recognise any signal when the switches are triggered.

The stepper motors work fine, I can run simple G code programs without any problems, but curiously when I try to jog the thing it pretty much crashes the PC.

I am using:

http://www.aliexpress.com/item/A16A-5-axis-CNC-Breakout-Board-interface-adapter-for-PC-Stepper-Motor-Driver-High-speed-optocoupler/363596507.html

http://www.acpd.co.uk/cgi-bin/site-editor.pl/8/-ecommerce?action=item;item=7230R011;eid=P422748

http://www.acpd.co.uk/cgi-bin/site-editor.pl/8/-ecommerce?action=item;item=ES1-00;eid=P422748

Any help would be much appreciated!

Offline Hood

*
  •  25,835 25,835
  • Carnoustie, Scotland
    • View Profile
Re: Help with input signals please
« Reply #1 on: July 09, 2014, 02:28:08 PM »
Do you have any documentation on that board?
Are you sure that it is Pin 10 that the board is connected to for the inpput you are using?

Please also attach your xml so I can check through your config.


Hood
Re: Help with input signals please
« Reply #2 on: July 10, 2014, 02:41:27 AM »
No documentation on the board other than a few bits of info on the website.

I have tried every pin and switch but still no luck. I have also tried with and without active low.

Thanks

Offline Hood

*
  •  25,835 25,835
  • Carnoustie, Scotland
    • View Profile
Re: Help with input signals please
« Reply #3 on: July 10, 2014, 03:28:31 AM »
I would suggest you try the auto setup of the inputs to see if you can get the input seen.
Normally I do not like using that but if you do not know what inputs the board uses it is probably the quickest way. If you get nothing when activating the switch whilst using the auto setup then check your wiring especially the port cable.
Hood
Re: Help with input signals please
« Reply #4 on: July 10, 2014, 04:21:15 AM »
The auto set-up is what wasn't working. The rig has been rewired and oddly the switches are now all recognised by mach3, it must have been a loose connection.

Mach3 continues to crash in constant vel jog mode, however step jogging works fine.

Another question - my stepper motors do 1/100" per step or 39.37mm per step. So If I run G code X+1, X-1. X0, surely the progam would take that as X+1 (39.37 x 1 = 39 steps), X-1 (39.37 x 2 = 79steps), X0 (39.37 x 1 = 39 steps), so at the end of the program it would be 1 step out of alignment? the resolution of my stepper motor will give me low accuracy?

Offline Hood

*
  •  25,835 25,835
  • Carnoustie, Scotland
    • View Profile
Re: Help with input signals please
« Reply #5 on: July 13, 2014, 04:37:26 PM »
Sorry dont follow regards your steppers.

Can you give some more info such as microstepping of drive. What gearing, if any, between motor and screw and pitch of screw.
Hood
Re: Help with input signals please
« Reply #6 on: July 15, 2014, 02:31:30 AM »
I used the automatic steps set-up.

When I use a high speed/vel I am loosing steps. Is there any way round it or is my hardware mechanically limited? I have no information on the maximum speed of the motor

Offline Hood

*
  •  25,835 25,835
  • Carnoustie, Scotland
    • View Profile
Re: Help with input signals please
« Reply #7 on: July 18, 2014, 02:33:04 PM »
It is hard to say what the issue could be, it may well be the motors are just not capable of the velocities you require or it could be something like a poor pulse from your computer. Run the drivertest and see if the line in the graph is smooth, if it has lots of spikes then that could be your problem.
Hood