http://www.debian.org/ports/arm/ says:
There are no plans to support older, really slow Acorn ARM-based
machines (using the ARM2 and ARM3 processors), although it is
possible. ELF support for these processors does not currently
exist.
How hard is it, then, to run Linux on an antique Archimedes with (I think) an
ARM3 processor? Which instruction set does the ARM3 use? What does no "ELF
support" mean? (Does it just mean there is no official value for e_machine?)
Edmund