Hi All,
Great to see PiBot is becoming active again.
I mentioned on Instagram about Z probing in GRBL on the PiBot CNC controller. I was never able to get this working on the 0.9g firmware version, was this feature supported on older versions or will it be supported on future firmware. I'm using universal gcode centre for control.
Thanks,
Adam
CNC Probing
Re: CNC Probing
Hi. sir, which gcode refer?
Re: CNC Probing
Hey Adam, could you please have more detail in the hardware and software you are using? Say the type of probe, to which port that been wired, the controller hardware version and firmware version, and the software and version. By having these information we can then reproduce your work condition and test. In fact we are implemeting 1.1e and this should up to be released shortly.
Re: CNC Probing
Hi, Sorry for the delay in responding. I have actually had some success with this now.
I had previously tried using a PiBot mechanical endstop plugged into the"CNC probing" 3 pin connector (the LED on the microswitch PCB would light but not trigger in software). Wirinf directly to the +5V and signal does occasionally work but will sometimes give "ALARM: Probe fail" which is usually caused by the switch starting in the wrong state (eg. reading 5V instead of 0V), I think this may be a noise/interference issue caused by the steppers.
Do you know of any solutions for reducing interference? I've been unable to get limit switches set up either for a similar reason, they would trigger while the machining is in normal operation.
Bit more information about my setup
GRBL 0.9g
PIBOT CONTROLLER BOARD REV2.0
4 x PIBOT STEPPER MOTOR DRIVER REV2.2
4 x Nema 23 1.9 Nm
24V power supply
Huanyang 1.5kw Air cooled spindle
I had previously tried using a PiBot mechanical endstop plugged into the"CNC probing" 3 pin connector (the LED on the microswitch PCB would light but not trigger in software). Wirinf directly to the +5V and signal does occasionally work but will sometimes give "ALARM: Probe fail" which is usually caused by the switch starting in the wrong state (eg. reading 5V instead of 0V), I think this may be a noise/interference issue caused by the steppers.
- Diagram Probe.png (173.05 KiB) Viewed 14456 times
Bit more information about my setup
GRBL 0.9g
PIBOT CONTROLLER BOARD REV2.0
4 x PIBOT STEPPER MOTOR DRIVER REV2.2
4 x Nema 23 1.9 Nm
24V power supply
Huanyang 1.5kw Air cooled spindle
- Attachments
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- IMG_20200807_145521361_HDR.jpg (230.46 KiB) Viewed 14456 times
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- IMG_20200807_145538878_HDR.jpg (208.76 KiB) Viewed 14456 times
Re: CNC Probing
Hi Mate, CNC Probing is an unbuffered direct input to the processor, and expect to use with an probing switch. If you like to use direct input like your diagram, would suggest:
1. Connect a pull-down resistor between S+ and GND, close to the controller board, a 10k Ohm resistor would does the job. This will ensure the processor pin at a stable level when seeing interference
2. Connect a diode, say 1N4148, from S+ to +5V, i.e. A to S+ and K to +5V. This will ensure the processor pin being protected from ESD or other interference.
3. If possible (only if possible), swap the polarity, workpiece at S+ and the mill bits at +5V. This is to prevent electromagnetic interference "jump" from motor winding directly to the shaft.
And don't forget to let us know how it goes.
1. Connect a pull-down resistor between S+ and GND, close to the controller board, a 10k Ohm resistor would does the job. This will ensure the processor pin at a stable level when seeing interference
2. Connect a diode, say 1N4148, from S+ to +5V, i.e. A to S+ and K to +5V. This will ensure the processor pin being protected from ESD or other interference.
3. If possible (only if possible), swap the polarity, workpiece at S+ and the mill bits at +5V. This is to prevent electromagnetic interference "jump" from motor winding directly to the shaft.
And don't forget to let us know how it goes.