USB Bridge CAN Firmware Flashing
SSH into the Host Computer
- Before compiling the firmware, use
wifi to connect to the host computer SSH
- First please: Use wifi to connect to the host computer SSH
- USB Bridge CAN Firmware Flashing
- Manually Compile USB Bridge CAN Firmware
USB Bridge CAN Firmware Flashing
- A USB bridge CAN firmware has been pre-compiled in the FLYOS-FAST system, no need to manually compile the firmware, execute the command below to flash
- You can also choose to
manually compile the USB bridge CAN firmware
and compile it yourself
-
Choose carefully according to your device, FLY system defaults to
1M
-
The C5 system defaults to 1M speed, if you need 500K, modify the
canbus_bitrate
speed in the system configuration -
This command flashes the
1M
USB bridge CAN firmware
fly-flash -d c5 -h -f /usr/lib/firmware/klipper-h723-128k-usbcan-1m.bin
- This command flashes the
500k
USB bridge CAN firmware
fly-flash -d c5 -h -f /usr/lib/firmware/klipper-h723-128k-usbcan-500k.bin


Manually Compile USB Bridge CAN 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, and then pressY
key whenSave configuration
appears
-
Now the configuration should be saved, and it returns to the command line interface
-
Enter the following command to start compiling, it takes some time
make -j4

- Finally, if the following content is output, the compilation is successful

Firmware Flashing
Execute the following command to flash the firmware
sudo fly-flash -d c5 -h -f ~/klipper/out/klipper.bin


Search for CAN ID
-
Open the browser and enter the IP address of the host computer in the address bar. For example, if my host computer's IP is
192.168.101.179
, just type it in and press Enter. -
Open the WEB interface of the host computer, find in the configuration options on the left sidebar:
- For fluidd:
{…}
, click to enter and you can findprinter.cfg
- For mainsail:
Machine
, click to enter and you can findprinter.cfg
- Click
printer.cfg
, then clickDEVICES
on the top right
- Click
CAN
, then refresh
- Refresh for fluidd
- Refresh for mainsail
- Copy the ID, click the arrow to copy
- For fluidd, confirm whether the first arrow points to
Klipper
, if yes, click the right arrow to copy
- For mainsail, confirm whether the first arrow points to
Klipper
, if yes, click the right arrow to copy
- For fluidd:
Fill in CAN ID
- Close
DEVICES
and fill in the ID
- Please modify the following content in the configuration file:
[mcu]
serial: /tmp/klipper_host_mcu
to
[mcu host]
serial: /tmp/klipper_host_mcu
- Add:
[mcu]
canbus_uuid: <Replace with the ID you just queried>
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- Fill in the ID in the configuration
- After filling in the ID, click
SAVE & RESTART
on the top right
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- If Klipper prompts
ADC out of range
, this is a normal phenomenon. Connect the heated bed and thermistor to the motherboard and configure the thermistor pins of the nozzle and heated bed, then save and restart.
Note: All IDs mentioned in the document are examples. Each motherboard has a different ID. Please fill in the actual obtained ID.