Bulldogg bootblock intro

In my previous post, I showed how the demo looks, and many of the choices I made while building it, now I thought I’d share more of the specifics of my small bootblock.

The regular boot stuff

As mentioned, there is a certain amount of boilerplate one needs to run if you are intending to continue to boot normally from a custom bootblock. There are lots of cases where you would load more parts using trackdisk.device (conviniently left in register A1 during bootblock execution!) or with a totally custom 0xDFFxxx disk loader solution, possibly with speedups, but for all the cases you are not doing this you need to do the boring stuff. As shown from the hexdump in the previous post, you have to reserve space for three longwords, and then do the dos.library and expansion library dance:

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Coding an Amiga bootblock demo

Once upon a time, me and my friends would be watching and later coding demos for the Amiga computers under the group name DeadZone. While there were many directions such demos would take, from small intros and cracktros to multiple-disk megademos, I quite liked to code bootblocks. The size challenge was a definite limit on what you could cram into those two sectors and still have a bootable disk.

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