Data gathering.

[tlhonmey]

So... I have one of these...
I have a copy of the Chinese software that comes with it...
I note that Wireshark these days can sniff USB traffic...

I don't know enough about CnC protocols to have a clear idea of what kind of model/gcode to feed into it to cover all the functions we'd want to capture...

If somebody can provide me with sample input to shove into the software that comes with it, I think I can collect the commands that get sent to the board, and then maybe we can figure out the protocol.

[tlhonmey]

Ok, so the Chinese software was utter garbage and I threw it away. Seriously, even hobbyists should demand better...

I looked at Mirecta's project for replacing the firmware and I've sorted out how to avoid needing to do the rewiring without needing massive software patches.

Now I'm just trying to figure out how to get the spindle motor to work, so if anyone else actually cares about this board anymore and can lend a hand figuring out which pins control the PWM output and how to control them I'd appreciate it.

[Sl0thie]

I just uploaded a project to https://github.com/Sl0thie/RE-BL-USBMach-2.1. I haven't got to the spindle yet but did notice a few bytes that seem to be related to the spindle. When using WireShark, the USB frames after initialization have the fourth byte varying when you change the spindle speed in Mach3.

[JeffHank1]

I have one of these too. It works well for Mach3 but I'd like to be able to reprogram the firmware for GrblHal. GrblHal has already been adapted for the Red Mach3 board commonly available. It looks like the 5 axis BL-USBMach-2.1 was created by the same person who has gone on to make the MKS TinyBee for example. I don't know if that person would be willing to share the pinout used for the Green Mach3 board or not. Macrobase-tech is his Github page. With a little digging some information about the green board is there but I don't know how to contact the person.

[tlhonmey]

https://github.com/tlhonmey/grbl

I've got this working without requiring hardware changes. I just can't seem to figure out for certain which pins off the STM32 processor chip actually control the spindle speed and in what way. I managed to find a combination of the likely candidates that turns the spindle full on, but any time I try to do PWM or anything with them it shuts down entirely.

Of course, my particular machine is tiny enough that it hardly matters, anything less than full speed is useless.

[JeffHank1]

Do you have a map of STM32 pins to the Mach3 board screw terminals you are willing to share? I’m curious about how you mapped them since I have no idea.

WRT VFD control it does seem necessary to use the 10v in reference pin to get a proper PWM signal to work. I’ve seen a couple YouTube videos discussing that aspect. Otherwise I prefer to twist the potentiometer myself = simpler.

[204-beilan]

https://oshwhub.com/jia_ming/mach3-interface-board
https://image-pro.lceda.cn/pullimages/9b147c9d5f3e4fb5a9eb69a252c91d17.webp
我查到了老版本的mach3并行板信息，但是他没有使用stm32，不清楚是否有帮助