Author Topic: XHC-MKX-IV Rev 5 issue controlling laser, JTechPhotonics Driver and PicConvert  (Read 543 times)

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Offline Vogavt

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The boards are all successfully talking to each other, well sorta.

I have an oddity with the XHC and the spindle output controlling the on/off of the laser itself. As a safety feature of the PicConvert board, I've wired from the XHC's Spindle Output#1 to the PicConvert Board input for enabling the laser only when a call is made from within the Gcode for an M03. I just happened to discover that issuing an M03 (normal start of the spindle) actually turns the laser OFF instead of ON. And M05 (normal stop) actually does the opposite.

I'm using Mach3 and I've unchecked and checked active low / active high for Spindle Output, OutPut #1, etc. to no avail.

For now I've swapped the M03 with an M05 at the start of the GCode and vice versa at the end of the file. Terrible workaround!

This means I have to make sure the spindle start command has been invoked BEFORE I turn on the laser. The Spindle has been removed and I've built a drop in laser attachment in its place. This way I can carve as needed then remove the spindle and start laser engraving the work-piece.

I haven't crossed swapped the wiring and don't want to do that, i.e., positive to negative. I have the positive out from the XHC going to the positive in to the PicConvert.

I tried other outputs on the XHC and made matching changes in Mach3 for those outputs on the spindle setup tab. I was unable to measure any appreciable voltage changes on those outputs when calling for an M03 or M05. Only Output #1 will work. However, I also discovered that I need to have power switched on to the VFD for the output #1 to enable the PicConvert to send signal to the laser via the JTechPhotonics driver.

The issue lies in the XHC-MKX-IV Rev5 board.

Has anyone seen this before or could give suggestions on how to make it more conventional?
I haven't even gotten to the M11P1 (ON) and M10P1 (OFF) yet.

The image below is in regards to voltages taken at Output #1.


I'm wondering if I need some sort of pull-up resistor.

I appreciate you all looking at this.