Games/Doom/amiga_sega.s

   1
   2                 .extern Sega6
   3                 .extern Sega3
   4
   5 # returns - xxSAxxxxxxCBMXYZxxSAxxDUxxCBRLDU
   6
   7                 .align  4
   8
   9 Sega6:          mflr    r8
  10                 lis     r7,0x00DF
  11                 lis     r6,0x00BF
  12                 ori     r7,r7,0xF000
  13                 ori     r6,r6,0xE001
  14
  15                 bl      GetSega         # xxSAxxDUxxCBRLDU
  16                 rlwinm  r3,r3,16,0,15   # save
  17                 bl      GetSega         # xxSAxxDUxxCBRLDU
  18                 bl      GetSega         # xxSAxxxxxxCBRLDU
  19                 bl      GetSega         # xxSAxxxxxxCBMXYZ
  20                 rlwinm  r3,r3,16,0,31   # xxSAxxxxxxCBMXYZxxSAxxDUxxCBRLDU
  21
  22                 li      r4,-0x0100      # SEL=1
  23                 mtlr    r8
  24                 sth     r4,0x34(r7)
  25                 blr
  26
  27 # returns - 0000000000000000xxSAxxDUxxCBRLDU
  28
  29                 .align  4
  30
  31 Sega3:          mflr    r8
  32                 lis     r7,0x00DF
  33                 lis     r6,0x00BF
  34                 ori     r7,r7,0xF000
  35                 ori     r6,r6,0xE001
  36
  37                 li      r3,0
  38                 bl      GetSega         # xxSAxxDUxxCBRLDU
  39
  40                 li      r4,-0x0100      # SEL=1
  41                 mtlr    r8
  42                 sth     r4,0x34(r7)
  43                 blr
  44
  45 # read Sega controller
  46
  47                 .align  4
  48
  49 GetSega:        rlwinm  r3,r3,0,0,15
  50                 li      r4,-0x00FF      # SEL=1, dump caps
  51                 sth     r4,0x34(r7)
  52
  53                 lbz     r4,0(r6)
  54                 lbz     r4,0(r6)
  55                 lbz     r4,0(r6)
  56                 lbz     r4,0(r6)
  57                 lbz     r4,0(r6)
  58                 lbz     r4,0(r6)
  59                 lbz     r4,0(r6)
  60                 lbz     r4,0(r6)
  61                 lbz     r4,0(r6)
  62                 lbz     r4,0(r6)
  63                 lbz     r4,0(r6)
  64                 lbz     r4,0(r6)
  65                 lbz     r4,0(r6)
  66                 lbz     r4,0(r6)
  67                 lbz     r4,0(r6)
  68                 lbz     r4,0(r6)
  69                 lbz     r4,0(r6)
  70                 lbz     r4,0(r6)
  71                 lbz     r4,0(r6)
  72                 lbz     r4,0(r6)
  73                 lbz     r4,0(r6)
  74                 lbz     r4,0(r6)
  75                 lbz     r4,0(r6)
  76                 lbz     r4,0(r6)
  77
  78                 rlwinm. r4,r4,0,24,24
  79                 bne     shl1
  80                 ori     r3,r3,0x10      # B/0
  81
  82 shl1:           lhz     r4,0x16(r7)
  83                 rlwinm. r4,r4,0,17,17
  84                 bne     shl2
  85                 ori     r3,r3,0x20      # C/0
  86
  87 shl2:           lhz     r4,0xC(r7)
  88                 rlwinm. r5,r4,0,30,30
  89                 beq     shl3
  90                 ori     r3,r3,8         # R/M
  91
  92 shl3:           rlwinm. r5,r4,0,22,22
  93                 beq     shl4
  94                 ori     r3,r3,4         # L/X
  95
  96 shl4:           rlwinm  r5,r4,1,0,31
  97                 xor     r4,r4,r5
  98                 rlwinm. r5,r4,0,30,30
  99                 beq     shl5
 100                 ori     r3,r3,2         # D/Y
 101
 102 shl5:           rlwinm. r5,r4,0,22,22
 103                 beq     shl6
 104                 ori     r3,r3,1         # U/Z
 105
 106 shl6:           li      r4,-0x10FF      # SEL=0, dump caps
 107                 sth     r4,0x34(r7)
 108
 109                 lbz     r4,0(r6)
 110                 lbz     r4,0(r6)
 111                 lbz     r4,0(r6)
 112                 lbz     r4,0(r6)
 113                 lbz     r4,0(r6)
 114                 lbz     r4,0(r6)
 115                 lbz     r4,0(r6)
 116                 lbz     r4,0(r6)
 117                 lbz     r4,0(r6)
 118                 lbz     r4,0(r6)
 119                 lbz     r4,0(r6)
 120                 lbz     r4,0(r6)
 121                 lbz     r4,0(r6)
 122                 lbz     r4,0(r6)
 123                 lbz     r4,0(r6)
 124                 lbz     r4,0(r6)
 125                 lbz     r4,0(r6)
 126                 lbz     r4,0(r6)
 127                 lbz     r4,0(r6)
 128                 lbz     r4,0(r6)
 129                 lbz     r4,0(r6)
 130                 lbz     r4,0(r6)
 131                 lbz     r4,0(r6)
 132                 lbz     r4,0(r6)
 133
 134                 rlwinm. r4,r4,0,24,24
 135                 bne     shl11
 136                 ori     r3,r3,0x1000    # A/0
 137
 138 shl11:          lhz     r4,0x16(r7)
 139                 rlwinm. r4,r4,0,17,17
 140                 bne     shl12
 141                 ori     r3,r3,0x2000    # S/0
 142
 143 shl12:          lhz     r4,0xC(r7)
 144                 rlwinm. r5,r4,0,30,30
 145                 beq     shl13
 146                 ori     r3,r3,0x800     # 0/1
 147
 148 shl13:          rlwinm. r5,r4,0,22,22
 149                 beq     shl14
 150                 ori     r3,r3,0x400     # 0/1
 151
 152 shl14:          rlwinm  r5,r4,1,0,31
 153                 xor     r4,r4,r5
 154                 rlwinm. r5,r4,0,30,30
 155                 beq     shl15
 156                 ori     r3,r3,0x200     # D/1
 157
 158 shl15:          rlwinm. r5,r4,0,22,22
 159                 beq     shl16
 160                 ori     r3,r3,0x100     # U/1
 161
 162 shl16:          blr
 163