Duet 3 expansion boards and tool boards have a bootstrap loader written to the start of flash so that they can load firmware from the main board via CAN. This bootloader may occasionally need to be updated in order to support new features. Here are two ways of doing so.
The bootloader can be downloaded from GitHub
.bin files are used when performing updates via CAN and can also be used when performing updates via Atmel ICE
.elf files were used when performing updates via Atmel ICE. Unfortunately the software (Atmel Studio or Microchip Studio) used to drive the ICE doesn't handle the .elf files generated by modern compilers; therefore we no longer suggest using the .elf files. Use the .bin files instead.
Here is a list of expansion boards and corresponding bootloader files:
| Board |
Bootloader file |
| Expansion 3HC, 1HCL, TOOL1RR, M23CL |
Duet3Bootloader-SAME5x.bin |
| Expansion 1XD, Toolboard 1LC, Scanning Z Probe |
Duet3Bootloader-SAMC21.bin |
| Sammy-C21 development board |
Duet3Bootloader-SAMMYC21.bin |
- You must be running RepRapFirmware 3.2.2 or later.
- Ensure that you have a stable power supply providing power to the Duet 3 main board and to the expansion board or tool board. If the power fails during the update process, the bootloader may be only partially written, in which case it will need to be updated using the second method.
- If you are updating the bootloader in-situ in a 3D printer or other machine, ensure that all motors are turned off using M18, and all fans, heaters and LEDs powered from the boards are turned off. That will maximise the reserve power in the event of a power cut while the bootloader is being updated.
- If you are updating a version 0.6 TOOL1LC board then we recommend that you disconnect the hot end heater before updating the bootloader. You can reconnect it (with power off) after the bootloader has been updated and you have checked that the tool board responds to commands.
- Upload the .bin file through the System page of DWC as if you are uploading a firmware file
- Update the bootloader using the M997 command with parameter S3 and the B parameter corresponding to the CAN address of the expansion or tool board. Example:
M997 B20 S3
14/11/2020, 19:01:25 M997 B20 S3
Board 20 starting bootloader update
To check the bootloader has been updated correctly you can send M122 Bnnn and the bootloader version will be displayed along with other diagnostic information:
M122 B11
Diagnostics for board 11:
Duet TOOL1LC firmware version 3.3beta2+1 (2021-03-20 14:03:00)
Bootloader ID: SAMC21 bootloader version 2.3 (2021-01-26b1)
If it reports Bootloader ID: not available then your board is using a version 1.x bootloader.
- Atmel ICE with firmware version 1.29 or later (check in "Tool Information" tab on Device programming in Atmel Studio 7).
- Windows PC running Atmel Studio 7 or Microchip Studio. It should also be possible to use Harmony but we have not tested this.
- If the tool or expansion board has a 6-pin JST ZH SWD connector, an adapter cable to connect the ICE to this connector.
- If the tool or expansion board does not have a 6-pin SWD connector then it will have 5 pads in line on the underside of the board with 2.54mm spacing. You can make contact to these using 5 pogo pins soldered to a piece of stripboard and use wires between the stripboard and the ICE.
The ICE uses a standard 2x5 1.27mm pitch JTAG/SWD connector. Breakout boards for this type of connector are readily available.
- Update the ICE firmware to latest version. The firmware on the ICE as it is supplied typically will not work for this purpose.
- Disconnect the CAN connector from the target board.
This is to prevent the old bootloader loading new firmware, which will immediately protect the old bootloader again.
- Connect the Atmel ICE to the 6-pin SWD connector on the target board, and to the PC via USB
- Power up the target board
- Load Atmel Studio or Microchip Studio on the PC
- Select Tools->Device Programming
- Select the ICE tool
- Select MCU type ATSAME51N19A for a EXP3HC expansion board, ATSAMC21G18A for a TOOL1LC or EXP1XD board, or ATSAME51J19A for a TOOL1RR board
- Press the Read button next to the Device Signature box and check that it reads the ID and voltage
- Select Memories
- Press the Erase Now button next to Erase Chip.
This erases the main firmware, but not the bootloader
- Select Fuses
- Find USER_WORD_0.NVMCRTL_BOOTPROT and set it to 0kbytes.
- Press Program to update the fuses.
- Select Memories
- Browse to the correct bootloader file for the target board, then press program. If using the .bin file then it will ask you for the memory address to start programming from; the default that it offers (normally zero) should be correct.
- Make sure the it reports verification succeeded.
- Power down the target system, disconnect the ICE and reconnect the CAN cable.
- When you apply power, the new bootloader will request firmware from the main board.
To check the bootloader has been updated correctly you can send M122 Bnnn and the bootloader version will be displayed along with other diagnostic information:
M122 B11
Diagnostics for board 11:
Duet TOOL1LC firmware version 3.3beta2+1 (2021-03-20 14:03:00)
Bootloader ID: SAMC21 bootloader version 2.3 (2021-01-26b1)