Are there any other devices on the hub? Want to make sure it’s the laser that you’re connecting to.
Do you see any messages in Console when LIghtBurn shows “Ready”?
What do your Device Settings look like?
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Jack, please forgive me… I’m not trying to be picky/mean but I can’t tell what you’re saying here.
You’ve referenced “it” 9 times in this statement and I’m really not sure what “it” is. And I’m really not sure what right-clicking the devics tab and “finding” it is all about. Once you’ve got a Grbl “device” defined/selected properly and you’re cabled to the board… I think the proper port should appear in the ports list. Select it and it should connect. That’s all I have to do with mine.
Beyond this, I’m really not sure how to help. Maybe someone else can jump in with new insight and/or more precise terminology?
– David
Ah! Thanks, guys, for jumping in… 
Sorry, speaking about the usb port. If I leave it at ‘choose’ or ‘auto’ it will find the device when I right click on the device button. That causes it to attempt to reconnect.
I know it’s the 1a86:7523 device… I know what the rest are…
Sorry, no. Looking for Edit->Device Settings which shows the baud rate and other connection settings.
Thanks @dkj4linux. Pretty straightforward.
@jkwilborn You may want to make sure that your settings are the same.
The only thing that could have been wrong is the baud rate. I’ve seen that enough to pick that out…
It just won’t connect and ‘screen’ doesn’t show anything either, so it’s not making it to the serial port at minimum.
The only thing I get out of it is
Waiting for connection...
Port failed to open - already in use?
Even though it displays ‘ready’ as the status. I don’t think Lightburn is looking at it the same way as I am…
The st-link seems to have loaded the image, tried both the bin and hex files. I suspect they are the same anyway…
Looks like I might have to dig around for something else… start of Sept I’m supposed to have the MK32 board here… I’d still like to get this board to work… it’s always nice to be able to generate pwm when you need it…
My setup is about as simple as I can make it. A direct connection… laptop USB to Cenoz machine. Have you tried just a simple connection… without a hub or other devices?
Do you have another gcode-sender application open to the machine?
Here’s my “lsusb”…
dkj4linux@penguin:~$ lsusb
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 028: ID 1a86:7523 QinHeng Electronics CH340 serial converter
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
dkj4linux@penguin:~$
Highly doubt it’s a usb issue… the problem is at the controller end.
I’ve used ‘screen’ with it and it just isn’t talking. Screen is a dumb terminal… so to speak…
The hubs are on my pci bus. They are not a problem… nothing is plugged into them…
@jkwilborn What’s the source of the GRBL_STM32.elf file that you loaded? Does that include a bootloader?
I assume you’d need to recover a bootloader and then load the firmware behind the bootloader but not sure what the contents of the ROM.bin file are.
It’s possible the firmware isn’t getting fully loaded.
Cr*p, I’m not sure now… I’ll have to run it down. I’m pretty sure, I compiled it from somewhere.
GRBL_STM32-master.zip.txt (1.9 MB)
I tried using the rom.bin that the others have used… same ol’ same ol’
My understanding is that the stm32 has a permanent boot loader, but I don’t know the chip well enough to know. I did do a chip erase in order to be able to write over the original code, so I could have blown it away…
I know enough to be dangerous with a atmel328p, but know little of the actual stm32… The docs take a while to wade through…
The st-link software has a group of boot loaders, but I’m not sure which is which. The part number doesn’t match…
A HUGE shout out and THANK YOU to David Johnson and Jack Wilborn for helping me out today.
I know it still needs some tweaking, but this is the best that I’ve produced in years.
Now if only I could get the jogging to work, I would be a happy camper.
For $80.00, this is a very nice machine.
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Hurrah! Mine came today. I will not be able to do anything with it until next week but at least I have one to play with now.
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From what I know if there’s definitely a user loadable bootloader. I think I saw that there were two bootloader paths, one system bootloader which is permanent and one user bootloader but not super familiar. User bootloader would be loaded at 0x0800000. This typically will provide the ability to flash from USB. Then firmware would be loaded at an offset off from the bootloader depending on the size of the bootloader. So if 32K bootloader then offset would be 0x08008000.
If you load the rom.bin to 0x0800000 it might work but not sure if the firmware needs to be compiled differently for that.
I have the stm32 document on boot loaders for the device, haven’t waded through it.
I think it is loading at 0x8000000
Isn’t the load address included in the binaries, generated at compile time?
The discussion on boot loaders maybe moot, as I’m loading it via st-link and not using the boot loader anyway… It’s probably the same game as the 328p isp interface.
Only thing I can think of in needing the boot loader is if it has something to do with communications interface that grbl uses for streaming grbl commands.
As far as I know, it’s running grbl fine, it’s just waiting for commands from a disabled communications port… 
All the motors are locked when it’s power up … good, bad or ugly.
The STM32 application will allow you to load any image to any location. However, I believe there can be hard-coded address references within the code. So if the firmware is not loaded at the expected offset it may not work. I don’t know if that’s necessarily the case here.
So if your laser is not working with ROM.bin being loaded at 0x08000000 then I’m assuming that it’s dependent on a bootloader starting it at a specific location. But I’m only speculating at this point.
Both of the .bin files I used show them starting at 0x8000000 location. However it’s clear that it can change where it loads.
If the ROM.bin file that is the upgrade is working for people, maybe I broke some other part of it.
If it won’t respond to the serial port, it’s lost… so that’s my first thing to fix.
There is another thread running about this… jl1-jl3-grbl-firmware-avialable
Probably what confused me about doing this… @LsrSal is using an ide that isn’t available on Linux. He did post some stuff and I may have to just start plugging at it…
I hate to not use the board for something, but I’m not going to spend a year figuring it out… My MKS32 board is a couple weeks away… the tracking shows it’s cleared customs.