LisaList2

General Category => LisaList2 => Topic started by: stepleton on March 31, 2020, 07:25:17 pm

Title: New: a hard drive bootloader and a low-level I/O library
Post by: stepleton on March 31, 2020, 07:25:17 pm
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!
Title: Re: New: a hard drive bootloader and a low-level I/O library
Post by: rayarachelian on March 31, 2020, 08:12:40 pm
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)
Title: Re: New: a hard drive bootloader and a low-level I/O library
Post by: stepleton on March 31, 2020, 08:23:36 pm
The thought had crossed my mind, but my style is pretty basic :-)
Interrupts shminterrupts...