Recore

Repository for Recore 3D printer control board

What is in here?

Schematics for Recore etc.
3D models of Recore
Device tree sources
Special binaries for booting the board in FEL mode
Calibration and testing data from the manufacturing process

Note about binaries

There are binaries for booting the board in FEL mode with a USB drive insered. This method bypasses the eMMC completely. The three files

sunxi-spl.bin
bl31.bin
u-boot.bin

are used to boot a board in FEL mode. See Makefile for instructions to use those for a specific revision.

The file configs/recore_fel_config is used to compile the new u-boot binaries, it is based on u-boot-v2022.07.

Sources

The binaries are identical to the what is used in Refactor/Rebuild distro, the source code is available here:
https://github.com/intelligent-agent/u-boot and
https://github.com/intelligent-agent/arm-trusted-firmware
The only differece is the boot command. In the stock image:
run distro_bootcmd
in the FEL binaries:
run bootcmd_usb0

Installing the sunxi-tools package.

In order to boot the board from FEL-mode, the program sunxi-fel must be available. In recent versions of Debian (Bookworm and later) and derivatives, this can be installed from apt.

sudo apt install sunxi-tools

On older versions of Debian, the sunxi-tools package does not have support for Allwinner A64. If that is the case, the program can be downloaded and installed with these instructions:

git clone https://github.com/linux-sunxi/sunxi-tools
cd sunxi-tools
make
sudo make install

Starting the board in FEL-mode

Hold down the button marked fel while applying power. The PMIC/power LED should come on. The board must be connected to a host computer through the USB C connector. When the board is in FEL-mode, it should show up as a USB device on the host computer:
lsusb
should show:
Allwinner Technology sunxi SoC OTG connector in FEL/flashing mode