PWM output on CNC BOB

[jolyonjenkins]

You are in the process of learning why cheap hardware is cheap and that some of what you are paying for with better, more expensive products is adequate documentation and support ;-)

Not the MOST helpful and specific piece of advice :-) I didn't buy this board, it came with a mill that someone else had retrofitted, and I am well aware of the danger of cheap hardware.
I did find a manual for it

https://www.dropbox.com/s/gfq4isvihn...rd-EN.pdf?dl=0

which I hope someone in the future might find useful

[Paul H]

Hi jolyonjenkins
Thanks for posting the BoB PDF i use these boards on my Boxford HMC160 CNC mill and Denford CNC Starturn lathe and they have performed well...
makes things easier...

Best regards
Paul

[ZASto]

Here is the manual for your BOB: https://warp9td.com/images/BOB_Vendo...line/ST-V2.pdf

[dazp1976]

I use these boards too. No issues. Pin 1 is the 0-10v / pwm, pin 17 is the on/off relay. You can then assign fwd/rev to pins 8,9 or16.
Board needs BOTH 5v and 12-24v psu's connected to the relevant inputs in order for it to work fully.

ONE THING TO WATCH. When I tried my output 1 it was backwards. So 10v was at stop and 0v was at max. Had to change active in Mach. Luckily I tested it with a voltmeter first lol.

[jolyonjenkins]

I'm probably being stupid here, but - I assume the relay is for switching the spindle on and off. At the moment I'm just getting my steppers to work, and testing with Linuxcnc and the stepconf wizard. All the steppers are working, but every time I click on "test this axis" the relay comes on, even before I jog the axis. Why is this? When using the machine for real, I would only want the relay to come on when I want the spindle on, not when moving an axis. I don't have the 24V supply connected atm, if that is relevant

[Clive S]

Can you post your hal and ini files

Also what Bob are you using and version of Linux

[dazp1976]

I'm probably being stupid here, but - I assume the relay is for switching the spindle on and off. At the moment I'm just getting my steppers to work, and testing with Linuxcnc and the stepconf wizard. All the steppers are working, but every time I click on "test this axis" the relay comes on, even before I jog the axis. Why is this? When using the machine for real, I would only want the relay to come on when I want the spindle on, not when moving an axis. I don't have the 24V supply connected atm, if that is relevant

Pin17 is the relay.
If you have seperate on/off & direction controls on the vfd:
Ports and pins I would suggest:
Spindle assign- step=pin 1, Dir=pin 16
Output #1 = pin17
Assign M3/M4 to output #1 (for on/off spindle)
Use pin16 for forward/reverse (I'd use a relay set up as NO=fwd / NC=rev)

Pin1 is the 0-10v/GND pins connected below where you plug in the 12-24v supply
Pin1 and all the other limit/estop inputs only work with this supply connected.
If you find that the ouput pin1 is 10v when stopped, change the active low/high level.


The relay also has a jumper next to it so you can change the output from the relay to screw terminal 17 instead.
Something like this anyway

[jolyonjenkins]

Here are my hal and ini files (I had to rename them as txt files to get them to upload).

The limit switches are all connected to machine ground except when they are pressed.
The estop switch is connected to ground if the machine is on, except when the button is pressed.

The steppers will all jog OK in stepconf. When I select an axis to test in stepconf, the BOB relay comes on (WHY?). When I run linuxcnc, the orange ON button is greyed out, even if I invert the estop input.

Should the limit switches and estop switches maybe be pulled high with resistors?

[Doddy]

Net xenable? - that's connected to par-port pin 17.

[dazp1976]

Net xenable? - that's connected to par-port pin 17.

That'll be why the relay is coming on when steppers asked to move.