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20 lines
466 B
C
20 lines
466 B
C
// http://codebase64.org/doku.php?id=base:small_fast_8-bit_prng
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int random_8(void) {
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static int seed=0x1f;
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static int newseed;
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newseed=seed; // lda seed
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if (newseed==0) goto doEor; // beq doEor
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newseed<<=1; // asl
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if (newseed==0) goto noEor; //beq noEor
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// if the input was $80, skip the EOR
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if (!(newseed&0x100)) goto noEor; // bcc noEor
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doEor:
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newseed^=0x1d; // eor #$1d
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noEor:
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seed=(newseed&0xff); // sta seed
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return seed;
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}
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