amiga_boottest
annotate src/boot/boot.s @ 1:48093e4bd99a
stuff
| author | John Tsiombikas <nuclear@member.fsf.org> |
|---|---|
| date | Wed, 21 Feb 2018 18:00:45 +0200 |
| parents | 51422ea54b9d |
| children | 58ebd84822e7 |
| rev | line source |
|---|---|
| nuclear@0 | 1 | vi:filetype=gas68k: |
| nuclear@0 | 2 .equ CMD_READ, 2 |
| nuclear@0 | 3 |
| nuclear@0 | 4 .equ EXEC_DO_IO, -0x1c8 |
| nuclear@0 | 5 |
| nuclear@0 | 6 | starting with trackdisk device I/O request pointer in a1 |
| nuclear@1 | 7 | load the program at 0x100 and jump there |
| nuclear@1 | 8 | program length is patched by mk_adf just before start |
| nuclear@0 | 9 start: |
| nuclear@1 | 10 move.l -6(%pc), %d0 | get binary size |
| nuclear@1 | 11 move.l %d0, 0x24(%a1) | I/O length |
| nuclear@0 | 12 move.l #0x100, 0x28(%a1) | I/O data pointer |
| nuclear@0 | 13 move.l #512, 0x2c(%a1) | I/O offset (skip first sector) |
| nuclear@0 | 14 move.w #CMD_READ, 0x1c(%a1) | I/O command |
| nuclear@0 | 15 move.l %a1, -(%sp) |
| nuclear@0 | 16 jsr EXEC_DO_IO(%a6) |
| nuclear@0 | 17 move.l (%sp)+, %a1 |
| nuclear@0 | 18 |
| nuclear@1 | 19 bra 0x100 |
| nuclear@0 | 20 .align 4 |