Sunday, 19 January 2014

The next game will be ... Space Invaders

Okay, so it's not horribly original. But it's a reasonable second game after the trial bomber game. This shows a mock up.

I decided against shields, because it would reduce the invaders space (err...) - there probably won't be any saucer across the top either.

There's a limit to what you can draw in a 16x16 grid !

I've also updated the bomber.asm and tms1100 assembler, so it can use include files - I did it just by concatenating the files together before but that meant the line numbers on the error messages were wrong.

A Thirty Year Event !

Yes, for the first time in thirty years (possibly because no-one else has been daft enough to do it) there's a new game for the Microvision.

It's one of those left to right Bombing the city flat games, where you have to clear a landing strip.

There are two keys - anything in the middle row drops a bomb, and anything on the left continues the game (when a level is over, because you've crashed or landed, it displays your score).

Source code has been added to the link list on the right. The assembler has also been updated (minor tweaks), the system library (ditto), and the Windows and OSX versions of the emulator (which contain the binary files).

Windows still has this clearing-one-byte behaviour (on resetting the TMS1100 it writes zero into code Memory [0]) that goes away with the insertion of an effectively null code line. I read through the code, and put a fair few ASSERTS in - I wondered if a rogue value got into X or Y and that caused a memory write , C not being protected, but can't see any problem. It's possible it might be in SDL of course.