From 1ef0d697a62eff28115d6642c850ba4d01ef6a89 Mon Sep 17 00:00:00 2001
From: "Juan J. Martinez" <jjm@usebox.net>
Date: Fri, 16 Sep 2022 07:34:44 +0100
Subject: Added CAS support to the example game

---
 game/src/crt0.z80 | 115 ++++++++++++++++++++++++++++--------------------------
 1 file changed, 60 insertions(+), 55 deletions(-)

(limited to 'game/src/crt0.z80')

diff --git a/game/src/crt0.z80 b/game/src/crt0.z80
index 81763d0..c8bd167 100644
--- a/game/src/crt0.z80
+++ b/game/src/crt0.z80
@@ -1,82 +1,87 @@
 .module crt0
-.globl	_main
 
-.area	_HOME
-.area	_CODE
-.area	_INITIALIZER
+.globl  _main
+
+.area   _HOME
+.area   _CODE
+.area   _INITIALIZER
 .area   _GSINIT
 .area   _GSFINAL
 
-.area	_DATA
-.area	_INITIALIZED
-.area	_BSEG
+.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
+.area   _CODE
+        ; ROM header
+        .str "AB"
+        .dw _main_init
+        .db 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+
+        ; entry point skipping the init code that is used
+        ; when starting from cassette
+        jp _cas_main
 
 _main_init::
 
-	; init the stack
-	di
-	ld sp, #0xf380
-	ei
+        ; init the stack
+        di
+        ld sp, #0xf380
+        ei
 
-	; setup memory
-	; ref: https://www.msx.org/forum/msx-talk/development/memory-pages-again
+        ; 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
+        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
+_cas_main::
+        ; disable key click sound
+        xor a
+        ld (CLIKSW), a
 
-	call gsinit
-	call _main
+        call gsinit
+        call _main
 
 halt0:
-	halt
-	jr 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
+        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
+        ret
-- 
cgit v1.2.3