HOMEBREW HEROES
Jon Williams surprised Atari Age forumites, posting to a discussion about the portability of his game Baby Berks before converting it for everyone to enjoy. We got in touch for a chat about his return to 8-bit coding
Where did the idea for converting Baby Berks to the Atari 8-bit come from?
I had always intended doing some more 6502 programming after retiring a few years ago. I recently managed to get all of my old source code from the Eighties converted to assembler on a PC IDE and this spurred me on. It was by chance that I noticed a thread on the Atariage forums suggesting that Baby Berks could be a candidate for porting to the Atari 8-bit – this was one of my C16 programs so it was the perfect way to refresh my memory on the hardware.
How long did it take to convert and what was involved?
It probably took two to three weeks in all but that was by no means full time. I use WUDSN so just copied the C16 source files into a new project and was up and running very quickly. I already had my Atari Timeslip code in WUDSN and it didn’t take long to copy across Atari specific code in place of the C16 routines. The C16 doesn’t have any hardware sprites so the main game code ran with surprisingly few changes. One challenge was in reducing the game character set from 256 to 128 characters. Fortunately, some of the characters were for the score, fuel indicator and game borders so with some rearranging I ended up with two sets switched a few times with Display
List Interrupts. Another task was to rework characters and code to get some more colour into the game – though it’s still not as colourful as the original.
What kind of feedback have you had so far from Atari 8-bit owners?
I’m not too sure how many people downloaded the game but I did get some favourable feedback on the forums.
Looking at the tools available now, how do they compare with the ones you used in the Eighties?
I’m really impressed with the tools that are available to programmers of all 8-bit machines. After some research I decided to use WUDSN on the Eclipse IDE. I chose this setup because it allowed me to work on my Atari, C64 and C16 projects with a single assembler – MADS. I couple my Atari development with the Altirra emulator, the source level debugging is an amazing advance over my setup from the Eighties. It’s a million miles from using Synassembler on my trusty Atari 800 with the assembled code being sent via the joystick ports to a target machine. I had to use Synassembler again to convert the original game source into modern format and the memories – and limitations – came flooding back.
And finally, have you got any future projects on the go that our readers might be interested in?
I’m just about to finish another C16 conversion to the Atari 8-bit, this is the second in the Berks trilogy, Major Blink. It’s very much an old-school game but a perfect way to revisit my old code. I intend to write something original after that and have a few ideas bubbling.