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remove obsolete function in neocrypt.c

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davidhay 2008-09-26 21:12:43 +00:00
parent c423c47d14
commit 448984121f
1 changed files with 0 additions and 33 deletions
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33
src/mame/machine/neocrypt.c
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@ -1452,39 +1452,6 @@ static const UINT8 m1_address_0_7_xor[256] =
}; };
int m1_address_scramble_inv(int address, UINT16 key)
{
int block;
int aux;
const int p1[8][16] = {
{8,4,5,6,15,14,12,3,7,13,2,10,9,11,1,0},
{13,1,6,7,10,8,14,0,2,5,12,3,15,9,11,4},
{9,7,10,3,8,11,1,5,0,15,4,13,14,12,2,6},
{10,12,0,4,5,15,9,7,1,3,11,6,13,8,14,2},
{14,0,13,5,9,12,2,10,6,8,7,15,11,1,4,3},
{5,11,7,2,3,13,8,4,12,6,14,0,10,15,9,1},
{11,6,15,10,14,1,4,13,3,9,0,8,12,2,7,5},
{3,14,4,1,6,10,15,2,11,0,9,7,5,13,8,12},
};
block = (address>>16)&7;
aux = address&0xffff;
aux = BITSWAP16(aux, 14,13,10,9,7,5,3,1,15,12,11,8,6,4,2,0);
aux ^= m1_address_8_15_xor[aux&0xff]<<8;
aux ^= m1_address_0_7_xor[(aux>>8)&0xff];
aux = BITSWAP16(aux,
p1[block][15],p1[block][14],p1[block][13],p1[block][12],
p1[block][11],p1[block][10],p1[block][9],p1[block][8],
p1[block][7],p1[block][6],p1[block][5],p1[block][4],
p1[block][3],p1[block][2],p1[block][1],p1[block][0]);
aux ^= key;
return (block<<16)|aux;
}
/* The CMC50 hardware does a checksum of the first 64kb of the M1 rom, /* The CMC50 hardware does a checksum of the first 64kb of the M1 rom,
,and uses this checksum as the basis of the key with which to decrypt ,and uses this checksum as the basis of the key with which to decrypt
the rom */ the rom */