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| author | Juan J. Martinez <jjm@usebox.net> | 2020-12-30 19:07:31 +0000 |
|---|---|---|
| committer | Juan J. Martinez <jjm@usebox.net> | 2020-12-30 19:23:41 +0000 |
| commit | 2682bc5d1d864341aaeb42a449db73c3ecd16d70 (patch) | |
| tree | 9116764364b4ee0ce7f6037305077807b57776de /game/src/crt0.z80 | |
| download | ubox-msx-lib-2682bc5d1d864341aaeb42a449db73c3ecd16d70.tar.gz ubox-msx-lib-2682bc5d1d864341aaeb42a449db73c3ecd16d70.zip | |
Initial import1.0
Diffstat (limited to 'game/src/crt0.z80')
| -rw-r--r-- | game/src/crt0.z80 | 82 |
1 files changed, 82 insertions, 0 deletions
diff --git a/game/src/crt0.z80 b/game/src/crt0.z80 new file mode 100644 index 0000000..81763d0 --- /dev/null +++ b/game/src/crt0.z80 @@ -0,0 +1,82 @@ +.module crt0 +.globl _main + +.area _HOME +.area _CODE +.area _INITIALIZER +.area _GSINIT +.area _GSFINAL + +.area _DATA +.area _INITIALIZED +.area _BSEG +.area _BSS +.area _HEAP + +.area _CODE + +ENASLT = 0x0024 +RSLREG = 0x0138 +CLIKSW = 0xf3db + + ; ROM header + .str "AB" + .dw _main_init + .db 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 + +_main_init:: + + ; init the stack + di + ld sp, #0xf380 + ei + + ; setup memory + ; ref: https://www.msx.org/forum/msx-talk/development/memory-pages-again + + call RSLREG + rrca + rrca + and #3 + ld c, a + add a, #0xc1 + ld l, a + ld h, #0xfc + ld a, (hl) + and #0x80 + or c + ld c, a + inc l + inc l + inc l + inc l + ld a, (hl) + and #0x0c + or c + ld h, #0x80 + call ENASLT + + ; disable key click sound + xor a + ld (CLIKSW), a + + call gsinit + call _main + +halt0: + halt + jr halt0 + +.area _GSINIT +gsinit:: + ld bc, #l__INITIALIZER + ld a, b + or a, c + jr Z, gsinit_next + ld de, #s__INITIALIZED + ld hl, #s__INITIALIZER + ldir +gsinit_next: + +.area _GSFINAL + ret |