mirror of
https://github.com/hsoft/collapseos.git
synced 2024-12-26 06:08:06 +11:00
118 lines
2.0 KiB
NASM
118 lines
2.0 KiB
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_SEL
|
|
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
|
|
ld de, 0 ; DE is used for seek > 64K which we don't support
|
|
call blkSeek
|
|
call blkTell
|
|
ld a, h
|
|
call printHex
|
|
ld a, l
|
|
call printHex
|
|
call printcrlf
|
|
xor a
|
|
ret
|
|
|
|
; Load the specified number of bytes (max 0x100, 0 means 0x100) from IO and
|
|
; write them in the current memory pointer (which doesn't change). If the
|
|
; blkdev hits end of stream before we reach our specified number of bytes, we
|
|
; stop loading.
|
|
;
|
|
; Returns a SHELL_ERR_IO_ERROR only if we couldn't read any byte (if the first
|
|
; call to GetC failed)
|
|
;
|
|
; Example: load 42
|
|
blkLoadCmd:
|
|
.db "load", 0b001, 0, 0
|
|
blkLoad:
|
|
push bc
|
|
push hl
|
|
|
|
ld a, (hl)
|
|
ld b, a
|
|
ld hl, (SHELL_MEM_PTR)
|
|
call blkGetC
|
|
jr nz, .ioError
|
|
jr .intoLoop ; we'v already called blkGetC. don't call it
|
|
; again.
|
|
.loop:
|
|
call blkGetC
|
|
.intoLoop:
|
|
ld (hl), a
|
|
inc hl
|
|
jr nz, .loopend
|
|
djnz .loop
|
|
.loopend:
|
|
; success
|
|
xor a
|
|
jr .end
|
|
.ioError:
|
|
ld a, SHELL_ERR_IO_ERROR
|
|
.end:
|
|
pop hl
|
|
pop bc
|
|
ret
|
|
|
|
; Load the specified number of bytes (max 0x100, 0 means 0x100) from the current
|
|
; memory pointer and write them to I/O. Memory pointer doesn't move. This puts
|
|
; chars to blkPutC. Raises error if not all bytes could be written.
|
|
;
|
|
; Example: save 42
|
|
blkSaveCmd:
|
|
.db "save", 0b001, 0, 0
|
|
blkSave:
|
|
push bc
|
|
push hl
|
|
|
|
ld a, (hl)
|
|
ld b, a
|
|
ld hl, (SHELL_MEM_PTR)
|
|
.loop:
|
|
ld a, (hl)
|
|
inc hl
|
|
call blkPutC
|
|
jr nz, .ioError
|
|
djnz .loop
|
|
.loopend:
|
|
; success
|
|
xor a
|
|
jr .end
|
|
.ioError:
|
|
ld a, SHELL_ERR_IO_ERROR
|
|
.end:
|
|
pop hl
|
|
pop bc
|
|
ret
|
|
|