Are you using macOS, Windows, Linux? Are you using a prebuilt copy of rpiboot or did you compile it yourself?
I’ve found the process to occasionally be flakey on macOS. I’d recommend disconnecting norns + USB cable from your computer, killing rpiboot, double checking that the switch is all the way over in disk mode, and then:
- run
rpiboot (norns disconnected)
- plug the USB cable into norns, then into your computer (trying a different USB port than you previously used)
- cross fingers
Some times it works for me the first time, other times I have to try 2-3 times. Eventually rpiboot will spit out something like the following:
Waiting for BCM2835/6/7
Sending bootcode.bin
Successful read 4 bytes
Waiting for BCM2835/6/7
Second stage boot server
File read: start.elf
Second stage boot server done
(As seen in macOS instructions linked in the top post).
UPDATE: I should add that I have found the latest version of rpiboot (compiled from source) fairly reliable with macOS Mojave