2007-06-04

Downtime

Not much going on here. The weather’s far too nice to sit around programming, and my project at work is finally drawing to a close (after nearly two years), so I’m getting bogged down in last-minute requests for changes that should really have been made earlier (ie. two years ago).

One thing I have managed to do is get E-UAE set up on my MacBook. It is noticably slower than even WinUAE in Parallels, but it does at least handle the mouse properly (not in AMOS, unfortunately). Drop the sound quality down to 8-bit and switch on OpenGL rendering and it’s not bad at all. This inspired me to get around to installing a real 68K assembler.

There are far too many assemblers available for the Amiga. I’d heard of DevPac, but there’s also Asm-One, Asm-Pro, PhxAss, SEKA, ArgAsm, and each one seems to come in multiple versions, often developed simultaneously by different people. Bit like DASM, I suppose, which seems to have slightly different versions available for different 6502 machines.

Anyway, I’ve given Asm-Pro a go, and it looks pretty good. Once I’d worked out how to get out of the weird commandline and into the editor, anyway. It’s a macro assembler, so it comes with macros to handle things like loops, IF blocks, etc. That’s something I wasn’t too keen on with the 6502 assemblers I looked at - if you’re going to use macros, why not just use a higher-level language? (I’ll probably end up writing out the op codes in hex myself at this rate.) The 68K chip is so much more complicated that I’m more inclined to use the macros. Factor in the massive difference in operating system complexity and custom chips and there’s really no choice - use macros or go mad.

So far, there are two hugely obvious differences between the chips. The 68K has an instruction set several times larger than the no-frills 6502. It’s also capable of handling 32-bit words, so adding two 16-bit numbers together doesn’t involve a dozen operations, the carry flag and a sacrificial goat.