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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,
,and uses this checksum as the basis of the key with which to decrypt
the rom */