USB to CAN Bridge Firmware Flashing
SSH into the Host Machine
- Firmware must be compiled before using
WiFi to connect to the host machine via SSH
- First, please: Use WiFi to connect to the host machine via SSH
- USB to CAN Bridge Firmware Flashing
- Manually Compile USB to CAN Bridge Firmware
USB to CAN Bridge Firmware Flashing
- A USB to CAN bridge firmware has already been pre-compiled in the FLYOS-FAST system. There is no need to compile the firmware manually; simply execute the command below to flash it
- You can also choose to
compile the USB to CAN bridge firmware manually
and compile the firmware yourself
-
Choose carefully according to your device; the FLY system defaults to
1M
-
The C5 system defaults to a rate of 1M. If you need 500K, you need to modify the
canbus_bitrate
rate in the system configuration -
This command flashes the
1M
USB to CAN bridge firmware
fly-flash -d auto -h -f /usr/lib/firmware/klipper-h723-128k-usbcan-1m.bin
- This command flashes the
500K
USB to CAN bridge firmware
fly-flash -d auto -h -f /usr/lib/firmware/klipper-h723-128k-usbcan-500k.bin


Manually Compile USB to CAN Bridge Firmware
Klipper Firmware Compilation and Configuration Page Operation Instructions
Please ensure that the keyboard input method is in half-width mode, i.e., English mode.
- The up arrow key
↑
, down arrow key↓
are used to move the cursor up and down to select menu items. - The confirm key
Enter
or space keySpace
is used to check the menu or enter a sub-menu. - The exit key
ESC
is used to return to the previous menu. - The
Q
key is used to exit the Klipper firmware configuration page. - The
Y
key, when exiting the Klipper firmware configuration page and there is a prompt, click theY
key to save the configuration file.
If there are fewer options in the configuration page, please first check [ ] Enable extra low-level configuration options
to display some hidden options.
Below is the introduction on how to compile the firmware:
-
After connecting to SSH, enter the following command and press Enter:
cd ~/klipper && rm -rf ~/klipper/.config && rm -rf ~/klipper/out && make menuconfig
-
Where
rm -rf ~/klipper/.config && rm -rf ~/klipper/out
is to delete previous compilation data and firmware,make menuconfig
is to compile the firmware, after execution, the following interface should appear -
Select Enable extra low-level configuration options and press Enter
-
Enter the menu Micro-controller Architecture then select STMicroelectronics STM32 and press Enter
-
Enter the menu Processor model, select STM32H723 and press Enter
-
Select Bootloader offset, select: 128KiB bootloader
-
Select Clock Reference (8 MHz crystal), select: 25 MHz crystal
-
Select Communication interface, select: USB to CAN bus bridge (USB on PA11/PA12)
- Press the
Q
key,Save configuration
will appear, then press theY
key
-
Now the configuration should be saved, and you will exit back to the command line interface
-
Enter the command below to start the compilation, which may take some time
make -j4

- The compilation is successful if the following content is output at the end

Firmware Flashing
Execute the following command to flash the firmware
fly-flash -d auto -h -f /data/klipper/out/klipper.bin


Search for CAN ID
- Open a browser and enter the IP address of the host computer in the address bar. For example, if the IP address of my host computer is
192.168.101.179
, simply enter it and press Enter.

- Open the WEB interface of the host computer, and in the configuration options of the left sidebar, find:
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-
After clicking into
printer.cfg
, click onDEVICES
in the upper right corner. -
Click
CAN
, then refresh.- Refresh in fluidd
- Refresh in mainsail
-
Copy the ID; click the arrow to copy it.
- In fluidd, confirm whether the item pointed to by the first arrow is
Klipper
; if so, click the arrow on the right to copy it.
- In mainsail, confirm whether the item pointed to by the first arrow is
Klipper
; if so, click the arrow on the right to copy it.
- In fluidd, confirm whether the item pointed to by the first arrow is
Fill in CAN ID
- Close
DEVICES
and fill in the ID
- Please change the following in the configuration file:
[mcu]
serial: /tmp/klipper_host_mcu
to
[mcu host]
serial: /tmp/klipper_host_mcu
- Add:
[mcu]
canbus_uuid: <Replace this with the ID you just looked up>
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- Fill the ID into the configuration
- After filling in the ID, click
SAVE & RESTART
in the upper right corner.
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- If Klipper shows a message
ADC out of range
, this is normal. Connect the heated bed and thermistor to the mainboard, and configure the thermistor pins for the extruder and heated bed, then save and restart.
Note: All IDs shown in the documentation are examples. Each mainboard has a different ID, so please fill in the actual ID you obtained.