Finally I got everything working with my Meadow ecosystem (powered by NuttX RTOS kernel)
First I flashed the basic core OS using DFU, as I explained in another post:
$ sudo dfu-util -a 0 -D Meadow.OS.bin -s 0x08000000Then I restarted the board and used the Meadow CLI to install the OS Runtime:
$ meadow mono update rt -f Meadow.OS.Runtime.bin -s /dev/ttyACM0
Connecting to Meadow on /dev/ttyACM0
An unknown request value of '0x4D00' was received.
Starting Mono Runtime Update
Meadow StdInfo: Mono is disabled
Connecting to Meadow on /dev/ttyACM0
Meadow StdInfo: Mono is disabled
Updating Mono Runtime
Starting File Transfer...
Meadow StdInfo: File 10% downloaded
Meadow StdInfo: File 20% downloaded
Meadow StdInfo: File 30% downloaded
Meadow StdInfo: File 40% downloaded
Meadow StdInfo: File 50% downloaded
Meadow StdInfo: File 60% downloaded
Meadow StdInfo: File 70% downloaded
Meadow StdInfo: File 80% downloaded
Meadow StdInfo: File 90% downloaded
Meadow StdInfo: Download of 'Meadow.OS.Runtime.bin' success (checksums calculated:0xC6FD7107, expected:0xC6FD7107)
Meadow StdInfo: Erasing mono flash memory
Meadow StdInfo: Mono memory erase success
Meadow StdInfo: Flashing 10% complete
Meadow StdInfo: Flashing 20% complete
Meadow StdInfo: Flashing 30% complete
Meadow StdInfo: Flashing 40% complete
Meadow StdInfo: Flashing 50% complete
Meadow StdInfo: Flashing 60% complete
Meadow StdInfo: Flashing 70% complete
Meadow StdInfo: Flashing 80% complete
Meadow StdInfo: Flashing 90% complete
Meadow StdInfo: Verifying runtime flash operation.
Meadow StdInfo: Verifying 10% complete
Meadow StdInfo: Verifying 20% complete
Meadow StdInfo: Verifying 30% complete
Meadow StdInfo: Verifying 40% complete
Meadow StdInfo: Verifying 50% complete
Meadow StdInfo: Verifying 60% complete
Meadow StdInfo: Verifying 70% complete
Meadow StdInfo: Verifying 80% complete
Meadow StdInfo: Verifying 90% complete
Meadow StdInfo: Mono runtime successfully flashed.
Transfer Complete, wrote 3145728 bytes to Meadow
Connecting to Meadow on /dev/ttyACM0
Mono Flashed Successfully
Done!