From: notaz <notasas@gmail.com>
Date: Sun, 26 Oct 2014 22:49:07 +0000 (+0200)
Subject: megaed-sv: move most start code to ROM
X-Git-Url: https://notaz.gp2x.de/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=bae3c7fdcbca9da77a40348cb74b4ae87c387a9d;p=megadrive.git

megaed-sv: move most start code to ROM
---

diff --git a/megaed-sv/asmtools.s b/megaed-sv/asmtools.s
index 2ed3df7..89eb3d0 100644
--- a/megaed-sv/asmtools.s
+++ b/megaed-sv/asmtools.s
@@ -243,109 +243,78 @@ run_game:
     movea.l     #0xc00000, a5
     movea.l     #0xc00005, a4
     movea.l     #0xc00004, a3
-    moveq.l     #0x00, d2
+    moveq.l     #0x00, d0
+    move.b      #0x40, d1     /* d2 is tmp */
     move.b      #0xff, d3
-    move.b      #0x40, d4
-    move.b      d4, (0x09,a6) /* CtrlA */
-    move.b      d2, (0x0b,a6) /* CtrlB */
-    move.b      d2, (0x0d,a6) /* CtrlC */
-    move.b      d2, (0x13,a6) /* S-CtrlA */
+    move.b      d1, (0x09,a6) /* CtrlA */
+    move.b      d0, (0x0b,a6) /* CtrlB */
+    move.b      d0, (0x0d,a6) /* CtrlC */
+    move.b      d0, (0x13,a6) /* S-CtrlA */
     move.b      d3, (0x0f,a6) /* TxDataA */
-    move.b      d2, (0x19,a6) /* S-CtrlB */
+    move.b      d0, (0x19,a6) /* S-CtrlB */
     move.b      d3, (0x15,a6) /* TxDataB */
-    move.b      d2, (0x1f,a6) /* S-CtrlC */
+    move.b      d0, (0x1f,a6) /* S-CtrlC */
     move.b      d3, (0x1b,a6) /* TxDataC */
 
     /* set up for vram write */
     move.l      #0x40000000, (a3)
 
     move.l      #0xff0000, a1
-    move.l      #0x10000/4/4-1, d0
+    move.l      #0x10000/4/4-1, d2
 0:
-    move.l      d2, (a1)+
-    move.l      d2, (a1)+
-    move.l      d2, (a1)+
-    move.l      d2, (a1)+
-    dbra        d0, 0b
-
-    move.l      #0xfffe00, a1
-    tst.l       d6
-    bne         use_tas_code
+    move.l      d0, (a1)+
+    move.l      d0, (a1)+
+    move.l      d0, (a1)+
+    move.l      d0, (a1)+
+    dbra        d2, 0b
 
     lea         (run_game_r,pc), a0
-    move.l      #(run_game_r_end - run_game_r)/2-1, d0
-    bra         0f
-use_tas_code:
-    lea         (run_game_r_tas,pc), a0
-    move.l      #(run_game_r_tas_end - run_game_r_tas)/2-1, d0
-
+    move.l      #0xffff80, a1
+    move.l      #(run_game_r_end - run_game_r)/2-1, d2
 0:
     move.w      (a0)+, (a1)+
-    dbra        d0, 0b
-    jmp         0xfffe00
-
-run_game_r:
-    move.w      #0x3210, (0xA13006)
-
-    move.w      d7, (0xA13010)
-    move.w      #0, (0xA13000)
-    
-    move.l      (0x00), a7
-    move.l      (0x04), a0
-    jmp         (a0)
-run_game_r_end:
-
-run_game_r_tas:
-    move.w      #0x3210, (0xA13006)
-    move.w      d7, (0xA13010)
-    move.w      #0, (0xA13000)
-    
-    move.l      (0x00), a7
-    move.l      (0x04), a0
+    dbra        d2, 0b
 
-0:  /* wait for special code */
-    move.b      d4, (0x03,a6)
-    move.b      (0x03,a6), d0
-    move.b      d2, (0x03,a6)
-    move.b      (0x03,a6), d1
-    and.b       #0x3f, d0
-    cmp.b       d0, d1
-    bne         0b
-    cmp.b       #0x25, d0
-    bne         0b
+    tst.l       d6
+    beq.s       0f
 
-0:  /* wait for special code to end */
-    cmp.b       (0x03,a6), d0
-    beq         0b
+    movea.l     #0xa10003, a0
+    movea.l     d0, a7
+    bsr         sync_with_teensy  /* trashes d3 */
+    move.l      d0, (-4,a7)
 
+0:
     /* wait for active display */
-    moveq.l     #3, d0
+    moveq.l     #3, d2
 0:
-    btst        d0, (a4)      /* 8 */
+    btst        d2, (a4)      /* 8 */
     beq.s       0b            /* 10 */
 0:
-    btst        d0, (a4)
+    btst        d2, (a4)
     bne.s       0b
 
     /* flood the VDP FIFO */
 .rept 5
-    move.w      d2, (a5)
+    move.w      d0, (a5)
 .endr
 
-    /* doesn't help.. */
-.if 0
-.rept 94
-    nop
-.endr
-    move.l      #0x93049400, (a3) /* DMALEN LO/HI = 0x0008 */
-    move.l      #0x95009601, (a3) /* DMA SRC LO/MID */
-    move.l      #0x977f8114, (a3) /* DMA SRC HI/MODE, Turn off Display */
-    move.l      #0xc0000080, (a3) /* start DMA */
-.endif
+    movea.l     d0, a0
+    movea.l     #0xA13000, a1
+
+    move.b      d0, (0x09,a6) /* CtrlA */
+    move.b      d1, (0x03,a6)
+
+    jmp         0xffff80
+
+run_game_r:
+    move.w      #0x3210, (0x06,a1) /* 0xA13006 */
+    move.w      d7, (0x10,a1)      /* 0xA13010 */
+    move.w      d0, (a1)           /* 0xA13000 */
+    
+    move.l      (a0)+, a7
+    move.l      (a0),  a0
 
-    move.b      d2, (0x09,a6) /* CtrlA */
-    move.b      d4, (0x03,a6)
     jmp         (a0)
-run_game_r_tas_end:
+run_game_r_end:
 
 # vim:filetype=asmM68k:ts=4:sw=4:expandtab