collapseos/kernel/blockdev_cmds.asm
Virgil Dupras 7fad3b0c90 Move /parts/z80 to /kernel
Let go of that "meta os" thing. it's not as meta as I made it sound
like. It's a kernel.
2019-05-19 11:19:41 -04:00

46 lines
721 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
push de
ld de, BLOCKDEV_GETC
call blkSel
pop de
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