MCU firmware on Sovol on mainline Klipper

Building the firmware

Mon, 01 Jan 0001 00:00:00 +0000

Building the firmware#

The MCU firmware (Katapult + Klipper) can be built either on the printer’s own host or on a Mac / Linux box, then the .bin copied over. Both produce identical images — pick whichever is handy.

Toolchain#

On the printer host (the Sovol Zero board’s Allwinner H616, Debian aarch64)#

arm-none-eabi-gcc is already installed — it’s the vendor’s own build chain. Clone the sources and build in place; no extra setup, and none of the macOS quirk below:

Flashing over SWD

Mon, 01 Jan 0001 00:00:00 +0000

Flashing over SWD with a Flipper Zero (DAP Link)#

The toolhead Katapult is request-only and can’t be recovered over CAN once an app is broken, so an SWD probe is the safety net. Any CMSIS-DAP probe works — an ST-Link V2 clone, or a Flipper Zero running the DAP Link app.

Verified scope. Everything here was tested only on the F103 toolhead, and only with a Flipper Zero (DAP Link app). An ST-Link should behave the same (it is standard SWD), and the H750 section below is reasoned, not tested. Corrections and additions are welcome — open a PR.

MCU migration

Mon, 01 Jan 0001 00:00:00 +0000

MCU migration — both MCUs onto mainline#

The clean way to put both MCUs fully on upstream Klipper — app and bootloader, no vendor bytes in the firmware. Build everything from the same Klipper master commit (see why master). The order is: build all four images, flash the toolhead once over SWD, then the mainboard over USB-Katapult.

Prerequisites#

An SWD programmer — ST-Link V2 (~$3 clone) or a Flipper Zero running the DAP Link app. Needed once, to bootstrap the toolhead: the vendor Katapult is request-only and can’t be recovered over CAN, so you flash a CAN-capable mainline Katapult onto the toolhead over SWD the first time, and never open the head again.
ARM toolchain — arm-none-eabi-gcc (already on the printer host) or brew install --cask gcc-arm-embedded on macOS. See Building the firmware.
openocd ≥ 0.11 for the SWD flash.
SSH access to the printer.

Back up first#

Before erasing anything, take your rollback — the SWD dump of the toolhead especially. The full backup checklist (vendor stack, SWD dump, eMMC image) is on the recovery page. The one that matters most here: