Thank you for all your responses,
The question about documentation is a very good one, and SLAA664 plus SLAU591A, available from their download page, does indeed seem a bit meager, documentation-wise. SLAA534, linked from them, seem to contain interesting reading material for an evening or two, and SLAU132J should keep me busy for the rest of the week. Is there anything else a beginner in this field should read up on? I often find statements such as "no biggie, just tweak the interrupts, and it works", which does sound encouraging. I'll just have to learn the old and new interrupt syntax,