The Neotron Pico BIOS supports defmt over RTT. Maybe it could expose a log write function. To avoid exposing defmt it would take a string slice, maybe supplemented with a slice of integers. That would cover most use cases. Other BIOS implementations could chuck it over a UART or something, or stick it a RAM buffer. The Desktop BIOS would printf it.
The Neotron Pico BIOS supports defmt over RTT. Maybe it could expose a log write function. To avoid exposing defmt it would take a string slice, maybe supplemented with a slice of integers. That would cover most use cases. Other BIOS implementations could chuck it over a UART or something, or stick it a RAM buffer. The Desktop BIOS would printf it.