USB Bridge CAN Firmware Flashing

SSH into the Host Computer

Warning

• Before compiling the firmware, you need to connect to the host computer SSH via Wi-Fi.

• First, please: Use Wi-Fi to Connect to the Host Computer SSH

• USB Bridge CAN Firmware Flashing
• Manually Compile USB Bridge CAN Firmware

USB Bridge CAN Firmware Flashing

Tip

• A USB Bridge CAN firmware has been pre-compiled in the FLYOS-FAST system, so manual compilation is not required. You can flash it by executing the command below.
• Alternatively, you can choose to Manually Compile USB Bridge CAN Firmware to compile the firmware yourself.

• The FAST system defaults to a 1M rate. If you need 500K, you need to modify the canbus_bitrate rate in the system configuration.

• This command flashes the 1M USB Bridge CAN Firmware:

fly-flash -d auto -h -f /usr/lib/firmware/klipper/stm32h723-128k-usbcan-1m.bin

• This command flashes the 500k USB Bridge CAN Firmware:

fly-flash -d auto -h -f /usr/lib/firmware/klipper/stm32h723-128k-usbcan-500k.bin

Loading...

Loading...

Firmware Compilation Quick Guide

Notes

• Network: Ensure the host machine (Raspberry Pi, etc.) is connected to the network.
• Login Method: Must use SSH to log in via the network; disable serial port.
• Input Method: Keep the keyboard in English half-width mode.

---

SSH Login and User Switching

Use tools like MobaXterm, PuTTY, etc., to SSH into the host machine.

Switching Users:

• Standard Systems (Raspberry Pi official system, etc.)
  Do not use root. Switch to a regular user:

  su <username>

• FLY Host Machine (FlyOS-FAST system)
  Only supports logging in as the root user (password: mellow).

---

Firmware Compilation Operation Guide

In the Klipper firmware configuration interface, only keyboard operations are supported; mouse usage is not possible.

Key	Function
↑ / ↓	Move the cursor up/down to select menu items
Enter / Space	Confirm selection, toggle options, or enter submenus
ESC	Return to the previous menu
Q	Exit the configuration interface
Y	When exiting, press Y if prompted to save the configuration

Start Firmware Compilation

The following describes how to compile the firmware:

• After connecting via SSH, enter the following command and press Enter:

  cd ~/klipper && rm -rf ~/klipper/.config && rm -rf ~/klipper/out && make menuconfig

• Here, rm -rf ~/klipper/.config && rm -rf ~/klipper/out deletes previous compilation data and firmware

• make menuconfig compiles the firmware. After execution, the following interface should appear

• Here, rm -rf ~/klipper/.config && rm -rf ~/klipper/out deletes previous compilation data and firmware, and make menuconfig compiles the firmware. After execution, the following interface should appear

  Loading...

• Select Enable extra low-level configuration options and press the Enter key

  Loading...

• Enter the Micro-controller Architecture menu, then select STMicroelectronics STM32 and press the Enter key

  Loading...

• Enter the Processor model menu, select STM32H723, and press the Enter key

  Loading...

• Select Bootloader offset and choose: 128KiB bootloader

  Loading...

• Select Clock Reference (8 MHz crystal) and choose: 25 MHz crystal

  Loading...

• Select Communication interface and choose: USB to CAN bus bridge (USB on PA11/PA12)

  Loading...

• Press the Q key, and when Save configuration appears, press the Y key
  Loading...
• The configuration should now be saved, and you will have exited to the command line interface
• Enter the following command to start compilation. This process may take some time.

make -j4

Loading...

• The compilation is successful if the following content is output at the end
• Due to Klipper version differences, the appearance of out/klipper.bin indicates success

  Linking out/klipper.elf
  Creating bin file out/klipper.bin

Firmware Flashing

Tip

Execute the following command to flash the firmware.

fly-flash -d auto -h -f /data/klipper/out/klipper.bin

Loading...

Loading...

---

Search for CAN ID

1. Open a browser, enter the IP address of the host computer in the address bar. For example, if the host IP is 192.168.101.179, simply type it in and press Enter.

Loading...

2. Open the WEB interface of the host computer. In the configuration options on the left sidebar, find:

For fluidd: {…}, click to enter, then find printer.cfg Loading...

For mainsail: Machine, click to enter, then find printer.cfg Loading...

3. Click printer.cfg to enter, then click DEVICES in the upper right corner.

   Loading...

   Loading...

4. Click CAN, then refresh.

   Refresh in fluidd Loading...

   Refresh in mainsail Loading...

5. Copy the ID. Click the indicated arrow to copy.

   In fluidd, ensure the first arrow points to Klipper. If yes, click the arrow on the right to copy. Loading...

   In mainsail, ensure the first arrow points to Klipper. If yes, click the arrow on the right to copy. Loading...

Fill in the CAN ID

1. Close DEVICES and fill in the ID.

Note

• In the configuration file, change:

[mcu]  
serial: /tmp/klipper_host_mcu  

to:

[mcu host]  
serial: /tmp/klipper_host_mcu  

• Add:

[mcu]  
canbus_uuid: <Replace here with the ID you just queried>  

Find [MCU] in fluidd Loading...

Find [MCU] in mainsail Loading...

2. Fill the ID into the configuration.

Tip

• After filling in the ID, click SAVE & RESTART in the upper right corner.

Loading...

Loading...

3. If Klipper prompts ADC out of range, this is normal. Connect the heated bed and thermistor to the mainboard, configure the thermistor pins for the nozzle and heated bed, then save and restart.

Danger

Note: All IDs appearing in this document are examples. The actual ID for each mainboard is different. Please fill in the ID you actually obtained.

---