Image writing to SSD/eMMC confusion

[spamwax]

Hi

Thanks for putting all these together. I have couple of questions:

• It Method 2, first step says "write the image to emmc"! If I am writing the image to emmc then I have an emmc that I can just pop to motherboard (like Method 1) and be done. What is the purpose of using an SD card then in Method 2?
• In step 5 of Method 2, I believe you are asking the user to ssh into the printer to use the fdisk and nand-sata-install commands, right? If that is the case, the guide can be more simplified by doing step 4 of method 2 entirely in linux
• In the Tip section of Step 4 about HDMI screen, are we using KIAUH to install klipperscreen or we should separately install it?
• What is the purpose of using a different Debian image? can we just erase Sovol's klipper and install the Mainline? we can then do the katapult and firmware upgrades

[Rappetor]

Hi there! Hope I can answer your questions! 😄

• Method 2 was originally made (mainly) because at the time some people were having issues with writing the image directly to the eMMC and for some weird reason they were successful when going the SD -> eMMC route instead. But I haven't heard this issue anymore after we changed the dtb files, so perhaps that was the issue behind it 🤔 But! Next to that, the idea also was you can give it a try on an SD card first and if everything works as you like (or perhaps the ordered eMMC is still on it's way) you can later move everything from the SD card to the eMMC in a more simple step.
• Step 5 of method 2 was only documented with using the eMMC usb adapter in Windows (thus the fdisk screenshots from there). But indeed, this could be done entirely from Linux (would make more sense as well). A nice person already took the time to document the steps needed to do this but I haven't had time yet to update this part 😊 . But again, the main reason why this entered the guide to begin with was because some people had issues writing the image directly to the eMMC (they would write the image, printer would not start). But it can now very well be an alternative to avoid buying the eMMC USB adapter.
• You can certainly use KIAUH to install Klipperscreen. The tip is there to avoid having to reboot twice (it's a tip coming from a community member who wondered why he had to reboot twice for no good reason 😛 ).
• Yep, this was the first way I installed mainline Klipper as well (remove the Sovol changed KIAUH and Klipper stuff, re-install KIAUH and go from there). But a lot of people seemed to struggle with removing/cleaning everything up from Sovol and have a good fresh start. In the beginning there were also some other random issues with this so it was decided to use this image as a base and make sure everyone has the same starting point going forward. It's the same image Sovol used as their base, so it's also nearly the same (well the V2.3.4 release not the new V3.0.0 obviously, we still need to get that working properly).

[spamwax]

thanks for the detailed explanation.
I am waiting for an adapter so I may try the SD card route and see what happens.

One more question, if I dont update the firmwares of main mcu and the toolhead and have no katapul, what steps will be needed if in the future the Klipper's firmware code (not the Python stuff) gets updated? Will I not be able to update the firmware at all or it will be a big hassle?

[Rappetor]

When you install mainline Klipper, but don't update the MCU's (especially currently the toolhead mcu), it might be you loose some functionality. Like the adxl sensor (for input shaper calibration) won't work anymore after a newer version of Klipper (that needs a mcu firmware update). But you can always disable that part in the config (edit, like we have done in the mainline guide printer.cfg, and then ask to enable it again after flashing the firmware) and then it will all still work. Must do the input shaper calibration manually then.

It's a little bit weird (or perhaps an inconvenient timing for them with the Klipper update) they released the printer with the current mcu firmware version of Klipper, because as soon as you update Klipper to a newer version it needs a mcu firmware update as well..

But in the future it could be some parts of Klipper might change that also need a mcu/firmware update. And so far the only way to update the mcu firmware is with the ST-Link (that is why we flash Katapult, so at least in the future the st-link is no longer needed to flash the mcu). I still hope Sovol might release some sort of firmware update in the future which allows the mcu's to be flashed without an st-link (like a method currently unknown to us, perhaps a file with a specific name like the mks board sometimes have).