mirror of
https://github.com/hsoft/collapseos.git
synced 2024-11-08 21:38:05 +11:00
07fde3cab5
It wasn't a good idea to complicate all blockdev impls with complicated seeks. Let's just stay in absolute mode for now.
43 lines
682 B
NASM
43 lines
682 B
NASM
; *** REQUIREMENTS ***
|
|
; blockdev
|
|
; stdio
|
|
|
|
blkBselCmd:
|
|
.db "bsel", 0b001, 0, 0
|
|
ld a, (hl) ; argument supplied
|
|
cp BLOCKDEV_COUNT
|
|
jr nc, .error ; if selection >= device count, error
|
|
call blkSel
|
|
xor a
|
|
ret
|
|
.error:
|
|
ld a, BLOCKDEV_ERR_OUT_OF_BOUNDS
|
|
ret
|
|
|
|
blkSeekCmd:
|
|
.db "seek", 0b001, 0b011, 0b001
|
|
; First, the mode
|
|
ld a, (hl)
|
|
inc hl
|
|
push af ; save mode for later
|
|
; HL points to two bytes that contain out address. Seek expects HL
|
|
; to directly contain that address.
|
|
ld a, (hl)
|
|
ex af, af'
|
|
inc hl
|
|
ld a, (hl)
|
|
ld l, a
|
|
ex af, af'
|
|
ld h, a
|
|
pop af ; bring mode back
|
|
call blkSeek
|
|
call blkTell
|
|
ld a, h
|
|
call printHex
|
|
ld a, l
|
|
call printHex
|
|
call printcrlf
|
|
xor a
|
|
ret
|
|
|