Has anyone tried running octoprint on the zim?

#1

i see a lot of discussion of running ocotpi on a raspberry pi to control the zim, but has anyone attempted to run octoprint on the board that’s already in the printer?

it’s a nice little board. 1Gb ram, 1.2GHz arm8, 4Gb flash. i spent a couple of weeks trying to log in via ssh and then by connecting a pl2303 serial adapter to the 4 pin header on the board. i’ve tried diddling /etc/shadow on 1.8.3 version of the software. ssh and the pl2303 both get me a login prompt, but i have no idea what the password is, and i’ve had no luck disabling it.

with the pl2303 attached i can watch the whole boot sequence. baud rate is 115200 if anyone is interested. and only connect ground, rx, and tx because the 5v from the pl2303 will kill your zim.

i even tried putting a plain debian release from cubieboard on an sd card and booting that. didn’t work, but i’m not sure why. i don’t really understand the boot process. i thought it would boot from sd if there was a bootloader on the card, but that doesn’t seem to be sufficient.

if anyone’s interested, here’s a picture of the connection of the pl2303 serial adapter to the zim. notice the black, green and white wires attached to the 4 pin header next to the white wifi adapter. once again, notice that the red 5v wire is not connected.

IMG_1628.JPG3264×2448 2.59 MB

#2

Baud rate is 250000 according to the firmware settings! :wink:

#3

pretty sure you’re talking about connecting to the controller board behind the right filament bay.

i’m talking about trying to login to the little linux server behind the left bay that runs the web interface. if you’ve removed the little black shield behind the filament bays you can see four pins sticking up next to where the wifi dongle and camera are plugged in to usb ports. this is the serial port to which i’ve connected. it does operate at 115200.

the board has twice the memory and runs about 25% faster than a raspberry pi b+. in addition to the two upwards pointing usb ports used for wifi and the camera, there is a miniusb port on the back of the board next to the ethernet connector. this port could be used to connect to the controller board if we could get octoprint running on the linux board.

i don’t know this for sure, but since the six wire connection between the server and the controller looks a whole lot like an avr isp connection, i’d guess that the two boards communicate using an spi interface. this would be useful for flashing new firmware to the controller. i haven’t dropped the bottom out of my zim, yet, but as far as i know, the six wire cable and the two wire power cable are the only connections between the two boards.

#4

The two boards communicate via uart at 250kbaud. Only two pins plus ground appear to be used between the cubie and the marlin board. I attached a logic analyzer between these a while back to sniff the serial commands zeepro was sending to marlin so I could create my own custom startup scripts for octoprint based upon their commands. The other pins appeared idle.

Since avr isp just connects to avr serial pins, you could be correct it doubles as the spi isp interface, and that would explain the extra pins. Though I would be very surprised if they did not leverage the arduino serial bootloader. Maybe they left this as an escape hatch for reflashing the bootloader.

#5

That awkward moment when you realize you are not understanding a Word of whats being said here…

3 Likes
#6

jpod,

that’s pretty interesting. i guess one of the other pins would be used to reset the marlin board for firmware updates.

are you running octoprint on the cubieboard? if not did you attempt it?

#7

I’ve only tried octoprint on the pi. I had a couple laying around so I thought I’d put them to good use. My cubie’s are collecting dust with Zeepro software in the nand flash.

#8

This has the potential to be the ideal way to divorce the Zim from Zeeproshare for the more faint of heart. An SD card image, and some way to get it to boot from same without a UART interface would be clean and painless.

jpod if I had one of your dusty Cubies I’d take a stab at bringing up Octoprint on it. PM me if I could have one – I’ll pay shipping of course.

I’d like to create an SD image and work out how to get the bootloader to load from it. Speaking of the bootloader – mtbf0 (funny handle btw) – did you notice any indication of what bootloader is being used during the boot sequence?