[pan69]

Memories.

If you're interested in this sort of thing there is one book you should read: Arm System on Chip by Steve Furber (original designer of the ARM)

http://www.amazon.com/ARM-System---Chip-Architecture-Edition...

[alexkus]

Brings back a lot of memories of assembly programming on the Acorn Archimedes[1] (ARM2 core) back in the early 90s.

It certainly was a revelation (all those registers!) after years of messing around with Z80/6502/80[123]?86.

1. https://en.wikipedia.org/wiki/Acorn_Archimedes