CAN Firmware Compilation

Start Compilation

Brief Guide to Firmware Compilation

Notes

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

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

Switch User:

Standard System (Official Raspberry Pi system, etc.)
Do not use root; switch to a regular user:
```
su <username>
```
FLY Host System (FlyOS-FAST system)
Only supports login as root user (password: mellow)

Firmware Compilation Operation Guide

In the Klipper firmware configuration interface, only keyboard operations are supported; the mouse cannot be used.

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

Where rm -rf ~/klipper/.config && rm -rf ~/klipper/out is to delete previous compilation data and firmware
make menuconfig is for compiling the firmware, after execution you should see the following interface

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Select Enable extra low-level configuration options and press Enter

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Enter the menu Micro-controller Architecture then select Raspberry Pi RP2040/RP235x and press Enter

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Select Bootloader offset, select:16KiB bootloader

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Select Communication interface, select:CAN bus

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Select (4) CAN RX gpio number, delete 4 and input 1
Select (5) CAN TX gpio number, delete 5 and input 0

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Select GPIO pins to set at micro-controller startup, input: gpio17
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Press the Q key, Save configuration will appear, then press the Y key

The configuration should now be saved and you will return to the command line interface
Enter the following command to start compiling, it will take some time

make -j4

The following output indicates successful compilation
Due to Klipper version issues, only the appearance of out/klipper.bin indicates success
```
Linking out/klipper.elf
Creating bin file out/klipper.bin
```

Search and Connect

Before flashing the firmware, connect the tool board to UTOC or a motherboard flashed with bridge firmware using an XT30 data cable. Refer to the wiring diagram below.
Please ensure the DIP switches are set to the correct positions.

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Ensure that the resistance between CAN H and CAN L is approximately 60Ω when measured with a multimeter while the power is off. If it is 120Ω, connect the 120Ω jumper. If it is around 40Ω, remove the jumper.

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After connecting the tool board to UTOC or a motherboard flashed with USB-to-CAN bridge firmware using an XT30 data cable, the LED on the motherboard will start blinking.

Warning

If the LED does not blink, please reflash the Katapult firmware: Flash Katapult Firmware
If the LED does not blink, proceed to the next step only after flashing the Katapult firmware.

Search ID and Flash

Querying CANBus UUID

Prerequisites

It is recommended to perform ID query and firmware flashing operations in a non-printing state to avoid interfering with the printing process.
The Katapult (CANBoot) firmware and Klipper firmware on the same mainboard/toolboard use the same CAN ID.

Prerequisites

Please ensure the following conditions are met, otherwise the CAN ID may not be found:

The host's CAN network is correctly configured
The toolboard's CAN baud rate is exactly the same as the host's (inconsistent baud rates will prevent communication)
Executing the lsusb command shows the 1d50:606f device (USB-CAN adapter)

Search Command (Choose based on system)

Standard host search command

~/klippy-env/bin/python ~/klipper/scripts/canbus_query.py can0

FLY host search command

python3 ~/klipper/scripts/canbus_query.py can0

Search Result Explanation

Case 1: Mainboard/Toolboard with Klipper Firmware Flashed

Display: Shows one CAN ID, with the prompt Application: Klipper
Explanation: The device is already running Klipper firmware and can be used directly. This ID could belong to the mainboard or the toolboard.
Differentiation Method: Disconnect the toolboard's CAN cable and search again. If the ID disappears, it belongs to the toolboard; if the ID remains, it belongs to the mainboard.

Case 2: Mainboard + Toolboard Ready for Flashing

Display: Shows two CAN IDs
Explanation: The mainboard runs Klipper firmware, and the toolboard runs CanBoot firmware, waiting to be flashed.

Case 3: UTOC + Toolboard Ready for Flashing

Display: The UTOC itself does not display an ID, only the toolboard's ID is shown
Explanation: The UTOC acts only as a bridge; ensure the toolboard is in CanBoot mode.

Case 4: No ID Displayed

Display: No IDs are shown
Possible Reasons:
1. The CAN bus is occupied by Klipper
2. Incorrect baud rate configuration on the host's CAN0 interface
3. Physical wiring issues
4. The device is not in CanBoot mode

Important Notes

Ready for Flashing State: When the toolboard is in CanBoot mode, it will display Application: CanBoot and the firmware LED will blink. Firmware flashing can be performed at this time.
ID Occupancy Handling: If a device is already running Klipper firmware and the ID has been entered in the configuration file, the ID will not be shown (occupied by Klipper). To display it again, you need to comment out the ID in the configuration and perform a complete power cycle.

Troubleshooting

If you cannot query the UUID, please refer to: CAN Issue Troubleshooting Guide

Firmware Flashing

Flash Command

Replace 241696050c56 in the command below with the UUID you actually queried
Note: A space is required after the -u parameter

python3 ~/klipper/lib/canboot/flash_can.py -u 241696050c56

Confirming Successful Flash

A CAN Flash Success prompt indicates successful flashing:

Firmware Update

Update Method

When a firmware update is required, simply:

Recompile the firmware
Ensure the device's CAN ID can be queried (or that Klipper is connected to the device)
Execute the same flashing command

python3 ~/klipper/lib/canboot/flash_can.py -u <MCU ID>

Update Success Example

Verify Firmware Startup

If the firmware starts normally, the LED will light up.
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Start Compilation​

Brief Guide to Firmware Compilation​

Notes​

SSH Login and User Switching​

Switch User:​

Firmware Compilation Operation Guide​

Start Firmware Compilation​

Search and Connect​

Search ID and Flash​

Querying CANBus UUID​

Search Command (Choose based on system)​

Search Result Explanation​

Case 1: Mainboard/Toolboard with Klipper Firmware Flashed​

Case 2: Mainboard + Toolboard Ready for Flashing​

Case 3: UTOC + Toolboard Ready for Flashing​

Case 4: No ID Displayed​

Firmware Flashing​

Flash Command​

Confirming Successful Flash​

Firmware Update​

Update Method​

Update Success Example​

Verify Firmware Startup​