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Hi,
I just finished configuring a shapeoko2 with a TinyG. I have been testing the limit switches and cannot get the X-Axis to fire on Min or Max. I did a homing test and whooops that was a bad idea…. did not fire off the X-Axis and had to e-stop the whole thing.
- Normally Close Switches
- Stepper Motors are Shielded
Testing Procedures tried:
- Metered Limit Switches For Open/Closed = OK
- Switched Limit Switches to Y-Axis on TinyG = OK
- Switched Y-Axis Limit Switches to X-Axis on TinyG = N/G
It would seem to me that the board is having a problem firing off the X-Axis Limits
I have attached the configuration as well.
Any help would be amazing!
Thanks so much,
MatthewConfiguration: https://www.dropbox.com/s/vcdgjibfjatot0y/tinyg.txt?dl=0
Howdy
Some quick items from visual scan of configuration:
1. Values of $xtr and $ytr look a bit unusual. NEMA 17s are usually 36.5ish, NEMA 23s usually 40.0ish (fine tune with good scale or micrometer)
2. You might want to set $xvm,xfr,yvm and yfr to something like 800 while you are in ‘bring up mode’, to give you time to react after issuing a move. Reset them to 16000 when you are satisfied everything is operating, or increment back up and keep checking machine dynamics while running some test GCode.But Neither of these comments directly addresses your limit issue.
By the way – if you machine bangs into a side, you can also hit the tinyG reset; which ever button is closer(reset or Emergency Stop). Either will stop the motors.
– Mechanical limit switches, or magnetic?
– When you say “Metered switches for open/closed”, was that at the switch or at the tinyG terminal block?
– Are you sure that the switches operate when X and Y are at the limits? You could simultaneously test the mechanical setup, the limit switches and your wiring by measuring the voltage on the tinyG pin with a voltmeter while you manually slide the axis toward the limits. If necessary, issue a $md first to release all motors. You should measure 0V when the machine is in the active area, 3.3V when a limit is hit.
– Your xsn, xsx, ysn, ysx, zsn and zsx parameters are sort of all over the place, I suspect you snapped this parameter set while experimenting. The suggested manual switch test above does not care about settings. Get limits working before trying homing.
– If all the switches pass the manual test, as measured at tinyG, set $xsn=2, $xsx=2, $ysn=2, $ysx=2. Zero your machine in the middle of the workspace. I usually manually move the gantry to where I want a zero point, then hit the reset button, zeroing the machine and re-enabling the motors. If your configs are correct, you will have about +-100mm in X, +-140mm in Y to play with while safely staying away from the rails. Now issue a G21 G1 X50 F100 command. This should initiate a slow(F100) move from the zero location to X=50mm. While the axis is moving,manually operate the X Limit switch, which should stop the gantry. Repeat for X-50, Y50, Y-50. After each quadrant test, you have to reset your zero.See if all these tests work.
4. The X-Axis does not pass the manual test. Even swapping the X and Y limit switches at the board to test known good switches (Y) on the X axis does not trigger on the board.
This seems to imply that the port pin is shorted to ground(same as NC),
Can I assume that you are probing the screw in the connector?
With no switch connected to the X limit connector, does the pin float high?
Make sure the screw is turned in to the empty connector position, or put your meter probe into the opening where the wire would go.
There is a 2.7K pull-up to 3.3V on each pin.
Flip look carefully at the board for solder overrun, etc from trace to gnd
Reference
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