M907 doesn't sent motor current?

Even though in the config file it was set 1.5, the motors were getting incredibly hot so I changed down to 0.5 And unknowingly they were still getting too hot. I was actually using the M907 command to set 0.3 thinking any lower and the motor would just simply not turn any more.

Unfortunately because this is a Flash forge dreamer case, the Z stepper got incredibly hot to the point it dropped out of the housing basically destroying the printer :frowning:

I did not realise until someone posted in another thread that is not Marlin compatible. It is one reason why I wanted to get rid of the flash forge board because it was just nothing standard. But I just seem to have swapped one bunch of problems for another :frowning:

I was starting to get the hang of the board for now I just have to buy a new printer :frowning:

Sorry to hear about the damage!

It’s possible to run Marlin on smoothieboards, but it’s not the default. Smoothieware and smoothieboards were developed together.

So this works

M907 X0.20000 Y0.20000 Z0.03000

I had Z at 0.30 originally. But that caused the motor to melt the mounts on my Flashforge dreamer. 0.03 I wouldn’t have thought that would even work. But works fine. I did try 0.1 yesterday, but the motor started to burn again. I dare not increase it anymore again.

from this thread which has the designer of both the smoothieboard and smoothieware providing the information, there just be only one M907 command, it should be in the config.txt file and there needs to be no M907 command in the GCode. ie the motor driver settings are loaded when the board boots, not after.

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Yeah but the M907 works just the same. I had to do that as changing the config file each time was turning into a nightmare. Mostly because I was just disconnecting the USB in windows, then unplugging the cable to kill power to the board to reboot it. But windows kept refusing to reconnect to the USB afterwards. So I had to keep rebooting which was just getting annoying.

I know there is reset commands etc, but I had the same problem. once the board “reset” windows wouldn’t find it again. I am still fighting that issue now in fact. I honestly hate windows and USB. USB has never been reliable. Never had issues with good old serial. I guess I could connect to LAN… but again windows… and the router to fight with.

are you saying you know for a fact that the firmware will dynamically switch the stepper motor driver power settings on the fly? Looked to me that the guy who wrote the Smoothieware software was saying to ONLY set the driver power in the firmware boot-up config.txt file and running the command multiple times will likely screw things up and/or not work.

If Windows is a PIA and you know a little about Linux then boot a LiveUSB and figure out your driver settings and then go back to Windows when you’re ready to use the machine. Otherwise, it sounds like you will have to reboot Windows every time you change your config.txt to tune your driver power levels.

Well the motor was burning hot before I sent M907, then it cooled down right down and still worked fine. That was repeatable a lot of times over the past month. So no idea why that thread says otherwise. If I had not been able to turn the current motor down the plastic would be melting again by now. The only warm motor is the extruder, but thats set at 0.7… which is about right (700mA) for the motor. Just I do get why the Z motor current setting seems to be x10 less than it should be.

In my main config file (when the Z was burning)

When I sent M907 and then did M500 to save (and it saved in config-override)

All I can say is that the guy who wrote the Smoothieware software said to put the M907 command in the config-override.txt file or else it would not be enabled. Since you did not do that and tried to set it only in config.txt(?) maybe that is why it defaulted to full current? He also said to only set it once.

Maybe you can find on the Smoothieware forum where his direction to set it only once and set it in config-override.txt has been superseded but without that, my recommendation is to follow what the author of the software says.

@Arthur_Wolf sometimes shows up here.