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-rw-r--r--src/mame/machine/spisprit.c281
1 files changed, 281 insertions, 0 deletions
diff --git a/src/mame/machine/spisprit.c b/src/mame/machine/spisprit.c
new file mode 100644
index 00000000000..422babfbdbd
--- /dev/null
+++ b/src/mame/machine/spisprit.c
@@ -0,0 +1,281 @@
+#if 0
+key tables: table[n] is the column of bit n
+cpu #0 (PC=0033C2F5): unmapped program memory dword write to 00000530 = 0000xxxx & FFFFFFFF (256 times, see key_table[])
+
+cpu #0 (PC=0033C315): unmapped program memory dword write to 00000524 = 843A0000 & FFFFFFFF
+cpu #0 (PC=0033C315): unmapped program memory dword write to 00000524 = 3A590000 & FFFFFFFF
+cpu #0 (PC=0033C315): unmapped program memory dword write to 00000524 = C8E20000 & FFFFFFFF
+cpu #0 (PC=0033C315): unmapped program memory dword write to 00000524 = 28D40000 & FFFFFFFF
+cpu #0 (PC=0033C315): unmapped program memory dword write to 00000524 = 9F840000 & FFFFFFFF
+cpu #0 (PC=0033C315): unmapped program memory dword write to 00000524 = 9CAC0000 & FFFFFFFF
+#endif
+
+
+#include "driver.h"
+// add two numbers generating carry from one bit to the next only if
+// the corresponding bit in carry_mask is 1
+static int partial_carry_sum(int add1,int add2,int carry_mask,int bits)
+{
+ int i,res,carry;
+
+ res = 0;
+ carry = 0;
+ for (i = 0;i < bits;i++)
+ {
+ int bit = BIT(add1,i) + BIT(add2,i) + carry;
+
+ res += (bit & 1) << i;
+
+ // generate carry only if the corresponding bit in carry_mask is 1
+ if (BIT(carry_mask,i))
+ carry = bit >> 1;
+ else
+ carry = 0;
+ }
+
+ // wrap around carry from top bit to bit 0
+ if (carry)
+ res ^=1;
+
+ return res;
+}
+
+/*
+This is the main key as written by the game.
+There are 256 values; the one to use is key_table[(address >> 8) & 0xff].
+
+Bits 0-3 select the permutation on 16 bits of the source data.
+Bits 4-14 are added to the source data, with partial carry.
+Bit 15 is still unknown.
+*/
+static const UINT16 key_table[256]=
+{
+ 0x3ad7,0x54b1,0x2d41,0x8ca0,0xa69b,0x9018,0x9db9,0x6559,
+ 0xe9a7,0xb087,0x8a5e,0x821c,0xaafc,0x2ae7,0x557b,0xcd80,
+ 0xcfee,0x653e,0x9b31,0x7ab5,0x8b2a,0xbda8,0x707a,0x3c83,
+ 0xcbb7,0x7157,0x8226,0x5c4a,0x8bf2,0x6397,0x13e2,0x3102,
+ 0x8093,0x44cd,0x5f2d,0x7639,0xa7a4,0x9974,0x5263,0x8318,
+ 0xb78c,0xa120,0xafb4,0x615f,0x6e0b,0x1d7d,0x8c29,0x4466,
+ 0x3f35,0x794e,0xaea6,0x601c,0xe478,0xcf6e,0x4ee3,0xa009,
+ 0x4b99,0x51d3,0x3474,0x3e4d,0xe5b7,0x9088,0xb5c0,0xba9f,
+ 0x5646,0xa0af,0x970b,0xb14f,0x8216,0x2386,0x496d,0x9245,
+ 0x7e4c,0xad5f,0x89d9,0xb801,0xdf64,0x8ca8,0xe019,0xde9b,
+ 0x6836,0x70e2,0x7dcd,0x7ac1,0x98ef,0x71aa,0x7d6f,0x70bd,
+ 0x9e14,0x75b6,0x8153,0xab6c,0x1f85,0x79cd,0xb2a1,0x934a,
+ 0x6f74,0x37d7,0xa05a,0x6563,0x1972,0x2dcd,0x7e59,0x6a60,
+ 0x5163,0x84c4,0xc451,0x8d80,0x4287,0x57e8,0xacc9,0x539d,
+ 0xbe71,0xdb7c,0x9424,0xb224,0xcc0f,0xe3dd,0xb79c,0x461e,
+ 0x96a9,0x4c7c,0x5443,0x6b2b,0x3cdc,0xbee8,0x2602,0x3282,
+ 0x7f9c,0x59c3,0xc69a,0x39f4,0x5138,0xb7ca,0x6ca7,0x62e7,
+ 0xc455,0x56cf,0x8a9a,0x695c,0x5af2,0xdebf,0x4dbb,0xdaec,
+ 0xb564,0xc89c,0x7d2d,0x6dc3,0xa15a,0x6584,0xb8ea,0xb7ac,
+ 0x88d8,0xc5aa,0x98c5,0xc506,0xc13c,0x7f59,0xab65,0x8fc8,
+ 0x3a3c,0xd5f6,0x554d,0x5682,0x8ce7,0x40fc,0x8fd7,0x535c,
+ 0x6aa0,0x52fe,0x8834,0x5316,0x6c27,0x80a9,0x9e6f,0x2c08,
+ 0x4092,0xc7c1,0xc468,0x9520,0xbc4d,0xb621,0x3cdb,0xdce8,
+ 0x481f,0xd0bd,0x3a57,0x807e,0x3025,0x5aa0,0x5e49,0xa29b,
+ 0xd2d6,0x7bee,0x97f0,0xe28e,0x2fff,0x48e4,0x6367,0x933f,
+ 0x57c5,0x28d4,0x68a0,0xd22e,0x39a6,0x9d2b,0x7a64,0x7e72,
+ 0x5379,0xe86c,0x7554,0x8fbb,0xc06a,0x9533,0x7eec,0x4d52,
+ 0xa800,0x5d35,0xa47d,0xe515,0x8d19,0x703b,0x5a2e,0x627c,
+ 0x7cea,0x1b2c,0x5a05,0x8598,0x9e00,0xcf01,0x62d9,0x7a10,
+ 0x1f42,0x87ce,0x575d,0x6e23,0x86ef,0x93c2,0x3d1a,0x89aa,
+ 0xe199,0xba1d,0x1b72,0x4513,0x5131,0xc23c,0xba9f,0xa069,
+ 0xfbfb,0xda92,0x42b2,0x3a48,0xdb96,0x5fad,0xba96,0xc6eb,
+};
+
+
+#if 0
+ { // table[15] NOT USED!
+ 0,0,0,1,1,1,1,0,1,1,1,1,1,0,0,1,1,0,1,0,1,1,0,0,1,0,1,0,1,0,0,0,
+ 1,0,0,0,1,1,0,1,1,1,1,0,0,0,1,0,0,0,1,0,1,1,0,1,0,0,0,0,1,1,1,1,
+ 0,1,1,1,1,0,0,1,0,1,1,1,1,1,1,1,0,0,0,0,1,0,0,0,1,0,1,1,0,0,1,1,
+ 0,0,1,0,0,0,0,0,0,1,1,1,0,0,1,0,1,1,1,1,1,1,1,0,1,0,0,0,0,1,0,0,
+ 0,0,1,0,0,1,0,0,1,0,1,0,0,1,0,1,1,1,0,0,1,0,1,1,1,1,1,1,1,0,1,1,
+ 0,1,0,0,1,0,1,0,0,0,1,0,0,1,1,0,0,1,1,1,1,1,0,1,0,1,0,1,0,0,0,1,
+ 1,0,1,1,0,0,0,1,0,0,0,1,0,1,0,0,0,1,0,1,1,1,0,0,1,0,1,1,1,0,0,0,
+ 0,0,0,1,1,1,0,0,0,1,0,0,1,1,0,1,1,1,0,0,0,1,1,1,1,1,0,0,1,0,1,1,
+ },
+#endif
+
+
+static const UINT8 bitswap[16][16] =
+{
+ { 15,14,13,12,11,10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0, },
+ { 7, 6, 5,14, 0,15, 4, 3, 2, 8, 9,10,11,12,13, 1, },
+ { 9,15,14,13,12, 0, 1, 2,10, 8, 7, 6, 5, 4, 3,11, },
+ { 5, 4, 3, 2, 9,14,13,12,11, 6, 7, 8, 1,15, 0,10, },
+ { 12,11, 0, 7, 8, 5, 6,15,10,13,14, 1, 2, 3, 4, 9, },
+ { 14, 0, 1, 2, 3, 9, 8, 7,15, 5, 6,13,12,11,10, 4, },
+ { 13,12,11,10, 2, 7, 8, 9, 0,14,15, 3, 4, 5, 6, 1, },
+ { 2, 9,10,11,12, 7, 6, 5,14, 3, 4, 0,15, 1, 8,13, },
+ { 8, 7, 4, 3, 2,13,12,11, 0, 9,10,14,15, 6, 5, 1, },
+ { 3, 2,10,11,12, 5,14, 0, 1, 4,15, 6, 7, 8, 9,13, },
+ { 2,10, 6, 5, 4,14,13,12,11, 1, 0,15, 9, 8, 7, 3, },
+ { 12,11, 8, 1,15, 3, 2, 9,10,13,14, 4, 5, 6, 7, 0, },
+ { 8, 7, 0,11,12, 5, 6,15,14, 9,10, 1, 2, 3, 4,13, },
+ { 3, 2, 1, 0,14, 9, 8, 7, 6, 4,15,13,12,11,10, 5, },
+ { 2,10,11,12,13, 7, 8, 9,15, 1, 0, 3, 4, 5, 6,14, },
+ { 12,11,10, 9, 2, 7, 6, 5, 4,13,14, 0,15, 1, 8, 3, },
+};
+
+
+static int key(int table,int addr)
+{
+ int xorbit = 8 + ((table & 0xc) >> 2);
+ return BIT(key_table[addr & 0xff] >> 4,table) ^ BIT(addr,xorbit);
+}
+
+
+void seibuspi_sprite_decrypt(UINT8 *src, int rom_size)
+{
+ int i;
+
+
+ for(i = 0; i < rom_size/2; i++)
+ {
+ int j;
+ int addr = i>>8;
+ int y1,y2,y3;
+ int s1,s2;
+ int add1,add2;
+ int plane0,plane1,plane2,plane3,plane4,plane5;
+ const UINT8 *bs;
+
+ y1 = src[2*i+0*rom_size+0] + (src[2*i+0*rom_size+1] << 8);
+ y2 = src[2*i+1*rom_size+0] + (src[2*i+1*rom_size+1] << 8);
+ y3 = src[2*i+2*rom_size+0] + (src[2*i+2*rom_size+1] << 8);
+
+
+ /* first of all, permutate 16 of the 48 bits */
+ bs = bitswap[key_table[addr & 0xff]&0xf];
+ y3 = BITSWAP16(y3, bs[0],bs[1],bs[2],bs[3],bs[4],bs[5],bs[6],bs[7],
+ bs[8],bs[9],bs[10],bs[11],bs[12],bs[13],bs[14],bs[15]);
+
+
+ // planes 4 & 5, interleaved
+ s1 = (BIT(y1, 4) << 0) |
+ (BIT(y3, 7) << 1) |
+ (BIT(y3, 6) << 2) |
+ (BIT(y2,12) << 3) |
+ (BIT(y2, 3) << 4) |
+ (BIT(y1,10) << 5) |
+ (BIT(y1, 1) << 6) |
+ (BIT(y3,14) << 7) |
+ (BIT(y3, 2) << 8) |
+ (BIT(y2, 9) << 9) |
+ (BIT(y2, 0) << 10) |
+ (BIT(y1, 7) << 11) |
+ (BIT(y3,12) << 12) |
+ (BIT(y2,15) << 13) |
+ (BIT(y2, 6) << 14) |
+ (BIT(y1,13) << 15);
+
+ add1 = (BIT(addr,11) << 0) |
+ (BIT(addr,10) << 1) |
+ (key(10,addr) << 2) |
+ (key( 5,addr) << 3) |
+ (key( 4,addr) << 4) |
+ (BIT(addr,11) << 5) |
+ (BIT(addr,11) << 6) |
+ (key( 7,addr) << 7) |
+ (key( 6,addr) << 8) |
+ (key( 1,addr) << 9) |
+ (key( 0,addr) << 10) |
+ (BIT(addr,11) << 11) |
+ (key( 9,addr) << 12) |
+ (key( 8,addr) << 13) |
+ (key( 3,addr) << 14) |
+ (key( 2,addr) << 15);
+
+ // planes 0-3, interleaved
+ s2 = (BIT(y1, 5) << 0) |
+ (BIT(y3, 0) << 1) |
+ (BIT(y3, 5) << 2) |
+ (BIT(y2,13) << 3) |
+ (BIT(y2, 4) << 4) |
+ (BIT(y1,11) << 5) |
+ (BIT(y1, 2) << 6) |
+ (BIT(y3, 9) << 7) |
+ (BIT(y3, 3) << 8) |
+ (BIT(y2, 8) << 9) |
+ (BIT(y1,15) << 10) |
+ (BIT(y1, 6) << 11) |
+ (BIT(y3,11) << 12) |
+ (BIT(y2,14) << 13) |
+ (BIT(y2, 5) << 14) |
+ (BIT(y1,12) << 15) |
+ (BIT(y1, 3) << 16) |
+ (BIT(y3, 8) << 17) |
+ (BIT(y3,15) << 18) |
+ (BIT(y2,11) << 19) |
+ (BIT(y2, 2) << 20) |
+ (BIT(y1, 9) << 21) |
+ (BIT(y1, 0) << 22) |
+ (BIT(y3,10) << 23) |
+ (BIT(y3, 1) << 24) |
+ (BIT(y2,10) << 25) |
+ (BIT(y2, 1) << 26) |
+ (BIT(y1, 8) << 27) |
+ (BIT(y3,13) << 28) |
+ (BIT(y3, 4) << 29) |
+ (BIT(y2, 7) << 30) |
+ (BIT(y1,14) << 31);
+
+ add2 = (key( 0,addr) << 0) |
+ (key( 1,addr) << 1) |
+ (key( 2,addr) << 2) |
+ (key( 3,addr) << 3) |
+ (key( 4,addr) << 4) |
+ (key( 5,addr) << 5) |
+ (key( 6,addr) << 6) |
+ (key( 7,addr) << 7) |
+ (key( 8,addr) << 8) |
+ (key( 9,addr) << 9) |
+ (key(10,addr) << 10) |
+ (BIT(addr,10) << 11) |
+ (BIT(addr,11) << 12) |
+ (BIT(addr,11) << 13) |
+ (BIT(addr,11) << 14) |
+ (BIT(addr,11) << 15) |
+ (BIT(addr,11) << 16) |
+ (key( 7,addr) << 17) |
+ (BIT(addr,11) << 18) |
+ (key( 6,addr) << 19) |
+ (BIT(addr,11) << 20) |
+ (key( 5,addr) << 21) |
+ (BIT(addr,11) << 22) |
+ (key( 4,addr) << 23) |
+ (BIT(addr,10) << 24) |
+ (key( 3,addr) << 25) |
+ (key(10,addr) << 26) |
+ (key( 2,addr) << 27) |
+ (key( 9,addr) << 28) |
+ (key( 1,addr) << 29) |
+ (key( 8,addr) << 30) |
+ (key( 0,addr) << 31);
+
+ s1 = partial_carry_sum( s1, add1, 0x3a59, 16 ) ^ 0x843a;
+ s2 = partial_carry_sum( s2, add2, 0x28d49cac, 32 ) ^ 0xc8e29f84;
+
+
+ // reorder the bits in the order MAME expects to decode the graphics
+ plane0 = plane1 = plane2 = plane3 = plane4 = plane5 = 0;
+ for (j = 0;j < 8;j++)
+ {
+ plane5 |= (BIT(s1, 2*j+1) << j);
+ plane4 |= (BIT(s1, 2*j+0) << j);
+ plane3 |= (BIT(s2, 4*j+3) << j);
+ plane2 |= (BIT(s2, 4*j+2) << j);
+ plane1 |= (BIT(s2, 4*j+1) << j);
+ plane0 |= (BIT(s2, 4*j+0) << j);
+ }
+
+ src[2*i+0*rom_size+0] = plane5;
+ src[2*i+0*rom_size+1] = plane4;
+ src[2*i+1*rom_size+0] = plane3;
+ src[2*i+1*rom_size+1] = plane2;
+ src[2*i+2*rom_size+0] = plane1;
+ src[2*i+2*rom_size+1] = plane0;
+ }
+}