I do all my SAM development on the PC, using a cross-assembler. For SAM development I chose the AS80 PC cross-assembler... Works a treat! It's free, and you can grab it here:
http://www.kingswood-consulting.co.uk/assemblers/ My editor of choice is StarBase's CodeWright 6.5 - which is great. It's not free though, and is a little tricky to find these days. For my initial foray into developing for the SAM - back in 1990(ish) - I used the SCAssembler, which can be found here: http://www.worldofsam.org/node/536 Then, when Edwin released his superb Comet assembler, I moved all my source over to that. Today - I would stick with developing on the PC though - it's much faster, and coupled with SimCoupé makes developing for the SAM a piece of cake! Chris.