mirror of
https://github.com/hsoft/collapseos.git
synced 2024-11-06 00:40:56 +11:00
126 lines
1.8 KiB
NASM
126 lines
1.8 KiB
NASM
; Glue code for the emulated environment
|
|
.equ RAMSTART 0x4000
|
|
.equ USER_CODE 0x4800
|
|
.equ STDIO_PORT 0x00
|
|
.equ STDIN_SEEK 0x01
|
|
.equ FS_DATA_PORT 0x02
|
|
.equ FS_SEEK_PORT 0x03
|
|
.equ STDERR_PORT 0x04
|
|
|
|
jp init ; 3 bytes
|
|
; *** JUMP TABLE ***
|
|
jp strncmp
|
|
jp addDE
|
|
jp addHL
|
|
jp upcase
|
|
jp unsetZ
|
|
jp intoDE
|
|
jp intoHL
|
|
jp writeHLinDE
|
|
jp findchar
|
|
jp parseHex
|
|
jp parseHexPair
|
|
jp blkSel
|
|
jp fsFindFN
|
|
jp fsOpen
|
|
jp fsGetC
|
|
jp fsSeek
|
|
jp fsTell
|
|
jp cpHLDE
|
|
jp parseArgs
|
|
|
|
#include "core.asm"
|
|
#include "err.h"
|
|
#include "parse.asm"
|
|
.equ BLOCKDEV_RAMSTART RAMSTART
|
|
.equ BLOCKDEV_COUNT 3
|
|
#include "blockdev.asm"
|
|
; List of devices
|
|
.dw emulGetC, 0, emulSeek, emulTell
|
|
.dw 0, emulPutC, 0, 0
|
|
.dw fsdevGetC, fsdevPutC, fsdevSeek, fsdevTell
|
|
|
|
.equ FS_RAMSTART BLOCKDEV_RAMEND
|
|
.equ FS_HANDLE_COUNT 0
|
|
#include "fs.asm"
|
|
|
|
init:
|
|
di
|
|
ld hl, 0xffff
|
|
ld sp, hl
|
|
ld a, 2 ; select fsdev
|
|
ld de, BLOCKDEV_GETC
|
|
call blkSel
|
|
call fsOn
|
|
ld hl, .zasmArgs
|
|
call USER_CODE
|
|
; signal the emulator we're done
|
|
halt
|
|
|
|
.zasmArgs:
|
|
.db "0 1", 0
|
|
|
|
; *** I/O ***
|
|
emulGetC:
|
|
in a, (STDIO_PORT)
|
|
or a ; cp 0
|
|
jr z, .eof
|
|
cp a ; ensure z
|
|
ret
|
|
.eof:
|
|
call unsetZ
|
|
ret
|
|
|
|
emulPutC:
|
|
out (STDIO_PORT), a
|
|
ret
|
|
|
|
emulSeek:
|
|
; the STDIN_SEEK port works by poking it twice. First poke is for high
|
|
; byte, second poke is for low one.
|
|
ld a, h
|
|
out (STDIN_SEEK), a
|
|
ld a, l
|
|
out (STDIN_SEEK), a
|
|
ret
|
|
|
|
emulTell:
|
|
; same principle as STDIN_SEEK
|
|
in a, (STDIN_SEEK)
|
|
ld h, a
|
|
in a, (STDIN_SEEK)
|
|
ld l, a
|
|
ret
|
|
|
|
fsdevGetC:
|
|
in a, (FS_DATA_PORT)
|
|
cp a ; ensure Z
|
|
ret
|
|
|
|
fsdevPutC:
|
|
out (FS_DATA_PORT), a
|
|
ret
|
|
|
|
fsdevSeek:
|
|
push af
|
|
ld a, e
|
|
out (FS_SEEK_PORT), a
|
|
ld a, h
|
|
out (FS_SEEK_PORT), a
|
|
ld a, l
|
|
out (FS_SEEK_PORT), a
|
|
pop af
|
|
ret
|
|
|
|
fsdevTell:
|
|
push af
|
|
in a, (FS_SEEK_PORT)
|
|
ld e, a
|
|
in a, (FS_SEEK_PORT)
|
|
ld h, a
|
|
in a, (FS_SEEK_PORT)
|
|
ld l, a
|
|
pop af
|
|
ret
|
|
|