Install CanBoot on SB2040

[Flob74]

Hi everyone !

I got a Voron 2.4 controlled with a RP3 and an Octopus board. I want to upgrade it with a SB2040 from Mellow Fly, connected directly to the Octopus's canbus port. (Use a U2C or a canhat would be too easy).

 

• I followed the FDMTeam's tutorial : how-to-use-can-toolhead-boards-connected-directly-to-octopus-octopus-pro-on-canboot
• I also found that the CanBoot project seems compatible with the RP2040 mcu : Issue to integrate the RP2040 to the canboot
• And I also complete voids with the  flash configuration recommended by Mellow Fly : SB2040 Flashing tutorial

But at the moment, Klipper can't connect to the octopus and the SB2040 seems unflashed (the blue LED which mean "firmware's running" remains off).

Sorry for the long post but, if it can help someone else, I have to detail everything. I did the following steps :

• Make a CanBoot bootloader for the Octopus
• Make a CanBoot bootloader for the SB2040
• Flash the Octopus with STM32Cube Programmer and the CanBoot bootloader
• Flash the SB2040 from the Raspberry PI and the Canboot bootloader
• Make a Klipper bootloader for the Octopus
• Make a Klipper bootloader for the SB2040
• Flash the Octopus with the Raspberry PI and the Klipper bootloader
• Flash the SB2040 throught the Octopus CanBus with the Klipper Bootloader
• Then I cried

The can0 interface is still setup (ifconfig), I got my two can_uuid :   [mcu] canbus_uuid: 3f56a5b6c36c ;  [mcu SB2040] canbus_uuid: 2d70e57a001c

But after I flashed the SB2040 through the canbus, his can_uuid disapeared. Of course, this probably comes from the fact that I can't use STM32Cube Programmer to make a "dual flash" ? I didn't truly understand the purpose of using STM32 Cube in that case.

I replaced the [mcu] section of the printer.cfg file with :

[mcu]
canbus_uuid: 3f56a5b6c36c

[mcu SB2040]
canbus_uuid: 2d70e57a001c

 

 

And the raspberry can't connect to the Octopus board. Klipper say : "mcu not available, try later". Not a surprise if Klipper is looking for the SB2040 mcu !

So, what did I miss ? Why after two flashs the SB2040 didn't have a firmware working ? Is there a software equivalent to STM32Cube to use with the RP2040 ?

 

Thank you for your help. I know that the Canboot project is very young, and I'm looking for troubles, but I hope that it will also help other peoples who face the same problem.

[danja]

CanBoot isn't critical for the printer to work, its a convenience feature that makes it possible to flash Klipper over the CANBUS. Without it you'd need to connect to USB every time you wanted to update.

If you have the tools, I just made my own adapter by crimping a RJ45 plug onto the CAN-H/L wires from the SB2040 loom. Works great, no adapter needed.

[mvdveer]

13 minutes ago, danja said:

by crimping a RJ45 plug onto the CAN-H/L wires from the SB2040 loom. Works great, no adapter needed.

Or use an old telephone jack and solder it to the high and low wires. I have installed to SB2040's now, one with the above and another with an adapter. I find the adapter bulky and the fit into the bus is not as secure as the telephone jack.

There are those that claim by soldering the can bus wires to the telephone jack, it will degrade the signal - in my case have not had an issue with time-outs or the like.

Again, use what you have available and what will work best for you.

[therm_virtual0y]

Is the SB 2040 better than the 2209?  Is it complicated to set up the spi with the main board being UART?  I’m trying to decide if I should get the BTT 2209, the 2040.  Also the U2C can take some load off the main board MCU I read?  Any pointers would be great.  

[mvdveer]

I think it is personal preference. I like the Mellow Fly products over the BTT products - no specific reason, just personal preference. Have the SB2040 on 4 Vorons and have not had any problems to date.  The SB2040 is a smaller footprint than the BTT 2209.