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

Then use the Makefile to run:
make fel