hexed/sega_gcc.s

   1 *-------------------------------------------------------\r
   2 *\r
   3 *       Sega startup code for the GNU Assembler\r
   4 *       Translated from:\r
   5 *       Sega startup code for the Sozobon C compiler\r
   6 *       Written by Paul W. Lee\r
   7 *       Modified from Charles Coty's code\r
   8 *\r
   9 *-------------------------------------------------------\r
  10 \r
  11         dc.l 0x0,0x200\r
  12         dc.l INT,INT,INT,INT,INT,INT,INT\r
  13         dc.l INT,INT,INT,INT,INT,INT,INT,INT\r
  14         dc.l INT,INT,INT,INT,INT,INT,INT,INT\r
  15         dc.l INT,INT,INT,HBL,INT,VBL,INT,INT\r
  16         dc.l INT,INT,INT,INT,INT,INT,INT,INT\r
  17         dc.l INT,INT,INT,INT,INT,INT,INT,INT\r
  18         dc.l INT,INT,INT,INT,INT,INT,INT,INT\r
  19         dc.l INT,INT,INT,INT,INT,INT,INT\r
  20         .ascii "SEGA GENESIS                    "\r
  21         .ascii "hexed (c) notaz, 2009                           "\r
  22         .ascii "HEXED (C) NOTAZ, 2009                           "\r
  23         .ascii "GM 00000000-00"\r
  24         .byte 0x00,0x00\r
  25         .ascii "JD              "\r
  26         .byte 0x00,0x00,0x00,0x00,0x00,0x02,0x00,0x00\r
  27         .byte 0x00,0xff,0x00,0x00,0xff,0xff,0xff,0xff\r
  28         .ascii "               "\r
  29         .ascii "                        "\r
  30         .ascii "                         "\r
  31         .ascii "JUE             "\r
  32 *debugee:\r
  33 *        bra     debugee\r
  34         tst.l   0xa10008\r
  35         bne     SkipJoyDetect                               \r
  36         tst.w   0xa1000c\r
  37 SkipJoyDetect:\r
  38         bne     SkipSetup\r
  39         lea     Table,%a5                       \r
  40         movem.w (%a5)+,%d5-%d7\r
  41         movem.l (%a5)+,%a0-%a4                       \r
  42 * Check Version Number                      \r
  43         move.b  -0x10ff(%a1),%d0\r
  44         andi.b  #0x0f,%d0                             \r
  45         beq     WrongVersion                                   \r
  46 * Sega Security Code (SEGA)   \r
  47         move.l  #0x53454741,0x2f00(%a1)\r
  48 WrongVersion:\r
  49         move.w  (%a4),%d0\r
  50         moveq   #0x00,%d0                                \r
  51         movea.l %d0,%a6                                  \r
  52         move    %a6,%usp\r
  53 * Set VDP registers\r
  54         moveq   #0x17,%d1\r
  55 FillLoop:                           \r
  56         move.b  (%a5)+,%d5\r
  57         move.w  %d5,(%a4)                              \r
  58         add.w   %d7,%d5                                 \r
  59         dbra    %d1,FillLoop                           \r
  60         move.l  (%a5)+,(%a4)                            \r
  61         move.w  %d0,(%a3)                                 \r
  62         move.w  %d7,(%a1)                                 \r
  63         move.w  %d7,(%a2)                                 \r
  64 L0250:\r
  65         btst    %d0,(%a1)\r
  66         bne     L0250                                   \r
  67 * Put initial values into a00000                \r
  68         moveq   #0x25,%d2\r
  69 Filla:                                 \r
  70         move.b  (%a5)+,(%a0)+\r
  71         dbra    %d2,Filla\r
  72         move.w  %d0,(%a2)                                 \r
  73         move.w  %d0,(%a1)                                 \r
  74         move.w  %d7,(%a2)                                 \r
  75 L0262:\r
  76         move.l  %d0,-(%a6)\r
  77         dbra    %d6,L0262                            \r
  78         move.l  (%a5)+,(%a4)                              \r
  79         move.l  (%a5)+,(%a4)                              \r
  80 * Put initial values into c00000                  \r
  81         moveq   #0x1f,%d3\r
  82 Filc0:                             \r
  83         move.l  %d0,(%a3)\r
  84         dbra    %d3,Filc0\r
  85         move.l  (%a5)+,(%a4)                              \r
  86 * Put initial values into c00000                 \r
  87         moveq   #0x13,%d4\r
  88 Fillc1:                            \r
  89         move.l  %d0,(%a3)\r
  90         dbra    %d4,Fillc1\r
  91 * Put initial values into c00011                 \r
  92         moveq   #0x03,%d5\r
  93 Fillc2:                            \r
  94         move.b  (%a5)+,0x0011(%a3)        \r
  95         dbra    %d5,Fillc2                            \r
  96         move.w  %d0,(%a2)                                 \r
  97         movem.l (%a6),%d0-%d7/%a0-%a6                    \r
  98         move    #0x2700,%sr                           \r
  99 SkipSetup:\r
 100         bra     Continue\r
 101 Table:\r
 102         dc.w    0x8000, 0x3fff, 0x0100, 0x00a0, 0x0000, 0x00a1, 0x1100, 0x00a1\r
 103         dc.w    0x1200, 0x00c0, 0x0000, 0x00c0, 0x0004, 0x0414, 0x302c, 0x0754\r
 104         dc.w    0x0000, 0x0000, 0x0000, 0x812b, 0x0001, 0x0100, 0x00ff, 0xff00                                   \r
 105         dc.w    0x0080, 0x4000, 0x0080, 0xaf01, 0xd91f, 0x1127, 0x0021, 0x2600\r
 106         dc.w    0xf977, 0xedb0, 0xdde1, 0xfde1, 0xed47, 0xed4f, 0xd1e1, 0xf108                                   \r
 107         dc.w    0xd9c1, 0xd1e1, 0xf1f9, 0xf3ed, 0x5636, 0xe9e9, 0x8104, 0x8f01                \r
 108         dc.w    0xc000, 0x0000, 0x4000, 0x0010, 0x9fbf, 0xdfff                                \r
 109 \r
 110 Continue:\r
 111         tst.w    0x00C00004\r
 112 \r
 113 * set stack pointer\r
 114 *        clr.l   %a7\r
 115         move.w   #0,%a7\r
 116 \r
 117 * user mode\r
 118         move.w  #0x2300,%sr\r
 119 \r
 120 * clear Genesis RAM\r
 121         lea     0xff0000,%a0\r
 122         moveq   #0,%d0\r
 123 clrram: move.w  #0,(%a0)+\r
 124         subq.w  #2,%d0\r
 125         bne     clrram\r
 126 \r
 127 *----------------------------------------------------------        \r
 128 *\r
 129 *       Load driver into the Z80 memory\r
 130 *\r
 131 *----------------------------------------------------------        \r
 132 \r
 133 * halt the Z80\r
 134         move.w  #0x100,0xa11100\r
 135 * reset it\r
 136         move.w  #0x100,0xa11200\r
 137 \r
 138         lea     Z80Driver,%a0\r
 139         lea     0xa00000,%a1\r
 140         move.l  #Z80DriverEnd,%d0\r
 141         move.l  #Z80Driver,%d1\r
 142         sub.l   %d1,%d0\r
 143 Z80loop:\r
 144         move.b  (%a0)+,(%a1)+\r
 145         subq.w  #1,%d0\r
 146         bne     Z80loop\r
 147 \r
 148 * enable the Z80\r
 149         move.w  #0x0,0xa11100\r
 150 \r
 151 *----------------------------------------------------------        \r
 152         jmp      main\r
 153 \r
 154 INT:    \r
 155         rte\r
 156 \r
 157 HBL:\r
 158         /* addq.l   #1,htimer */\r
 159         rte\r
 160 \r
 161 * VBL:\r
 162 *       addq.l #1,(vtimer).l\r
 163 *       rte\r
 164 \r
 165 *----------------------------------------------------------        \r
 166 *\r
 167 *       Z80 Sound Driver\r
 168 *\r
 169 *----------------------------------------------------------        \r
 170 Z80Driver:\r
 171           dc.b  0xc3,0x46,0x00,0x00,0x00,0x00,0x00,0x00\r
 172           dc.b  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00\r
 173           dc.b  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00\r
 174           dc.b  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00\r
 175           dc.b  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00\r
 176           dc.b  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00\r
 177           dc.b  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00\r
 178           dc.b  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00\r
 179           dc.b  0x00,0x00,0x00,0x00,0x00,0x00,0xf3,0xed\r
 180           dc.b  0x56,0x31,0x00,0x20,0x3a,0x39,0x00,0xb7\r
 181           dc.b  0xca,0x4c,0x00,0x21,0x3a,0x00,0x11,0x40\r
 182           dc.b  0x00,0x01,0x06,0x00,0xed,0xb0,0x3e,0x00\r
 183           dc.b  0x32,0x39,0x00,0x3e,0xb4,0x32,0x02,0x40\r
 184           dc.b  0x3e,0xc0,0x32,0x03,0x40,0x3e,0x2b,0x32\r
 185           dc.b  0x00,0x40,0x3e,0x80,0x32,0x01,0x40,0x3a\r
 186           dc.b  0x43,0x00,0x4f,0x3a,0x44,0x00,0x47,0x3e\r
 187           dc.b  0x06,0x3d,0xc2,0x81,0x00,0x21,0x00,0x60\r
 188           dc.b  0x3a,0x41,0x00,0x07,0x77,0x3a,0x42,0x00\r
 189           dc.b  0x77,0x0f,0x77,0x0f,0x77,0x0f,0x77,0x0f\r
 190           dc.b  0x77,0x0f,0x77,0x0f,0x77,0x0f,0x77,0x3a\r
 191           dc.b  0x40,0x00,0x6f,0x3a,0x41,0x00,0xf6,0x80\r
 192           dc.b  0x67,0x3e,0x2a,0x32,0x00,0x40,0x7e,0x32\r
 193           dc.b  0x01,0x40,0x21,0x40,0x00,0x7e,0xc6,0x01\r
 194           dc.b  0x77,0x23,0x7e,0xce,0x00,0x77,0x23,0x7e\r
 195           dc.b  0xce,0x00,0x77,0x3a,0x39,0x00,0xb7,0xc2\r
 196           dc.b  0x4c,0x00,0x0b,0x78,0xb1,0xc2,0x7f,0x00\r
 197           dc.b  0x3a,0x45,0x00,0xb7,0xca,0x4c,0x00,0x3d\r
 198           dc.b  0x3a,0x45,0x00,0x06,0xff,0x0e,0xff,0xc3\r
 199           dc.b  0x7f,0x00\r
 200 Z80DriverEnd:\r
 201 \r
 202 \r