Hi list, I hope you're all doing well...
I've made two new low-level software items for Lisa. First, there's a hard drive bootloader:
https://github.com/stepleton/bootloader_hd (https://github.com/stepleton/bootloader_hd)
It's not too sophisticated: it doesn't know about filesystems, and it works a lot like my floppy bootloader (https://github.com/stepleton/bootloader) --- it just loads blocks into RAM, starting from block $000002 until it sees it should stop.
The bootloader uses the second project: a low-level I/O library in 68k assembly that I've started here:
https://github.com/stepleton/lisa_io (https://github.com/stepleton/lisa_io)
Right now it has components for keyboard and mouse input, fixed-width text display on the screen, and reads/writes to parallel port hard drives. No floppy or serial port support yet---maybe someday later.
You can see a boring demonstration of both on YouTube here:
https://www.youtube.com/watch?v=4WP4kkj1mRM (https://www.youtube.com/watch?v=4WP4kkj1mRM)
I hope these will be useful. Please stay safe!
Yeay! Glad it's published!
You know this is how operating systems get written, they start out as small tiny things like bootloaders, or in the case of Linux, a terminal program. :)
(hint hint)
The thought had crossed my mind, but my style is pretty basic :-)
Interrupts shminterrupts...