rumbac is a simple commandline tool for uploading .bin files with compiled programs to the Arduino Nano 33 BLE Rev2 or ... Sense Rev2 board (with the nRF52840 microcontroller).

The boards come preprogrammed with a builtin bootloader, communicating over a serial port over USB. The protocol used for that is a very simple, text-based one, called "SAM-BA". rumbac implements a very minimal subset of that protocol, just enough to allow flashing a .bin file to one of those supported boards. The implementation is based on a popular bossac tool, in a variant forked by the Arduino team for the Nano board.

Note: the tool does not currently implement variants of the "SAM-BA" protocol for any other boards, because I don't own them, and thus cannot test. If you'd like to have support added for your favourite bossac-compatible board, this project is open to contributions/forks - or, you could send me a specimen of that board and I will try to add it.

To install the tool, run:

cargo install --git https://github.com/akavel/rumbac

An example usage session then looks like below:

Remember to first double-press the button on the device such that the LED will start pulsating.

C:> rumbac
Found 1 serial port:
 "COM13" = UsbPort(UsbPortInfo { vid: 9025, pid: 90, serial_number: Some("00000000000000007F65FDABFE86A5EB"), manufacturer: Some("Microsoft"), product: Some("Urządzenie szeregowe USB (COM13)") })
C:> rumbac COM13
Initializing "COM13"...
> "V#"
< "Arduino Bootloader (SAM-BA extended) 2.0 [Arduino:IKXYZ]\n\r"
> "I#"
< "nRF52840-QIAA\n\r"
Feats { chip_erase: true, write_buffer: true, checksum_buffer: true, identify_chip: true, reset: true }
Flash { name: "nRF52840-QIAA", addr: 0, pages: 256, size: 4096, planes: 1, lock_regions: 0, user: 0, stack: 0 }
C:> rumbac COM13 myprogram.bin
Initializing "COM13"...
> "V#"
< "Arduino Bootloader (SAM-BA extended) 2.0 [Arduino:IKXYZ]\n\r"
> "I#"
< "nRF52840-QIAA\n\r"
> "N#"
< "\n\r"
> "S00000000,00001000#"
> "Y00000000,0#"
< "Y\n\r"
> "Y00000000,00001000#"
< "Y\n\r"
> "K#"

The device should now automatically disconnect and start running the newly flashed program.