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29 lines
564 B
NASM
29 lines
564 B
NASM
; Part of kernel because ideally we have some sort of entropy. For now,
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; just having it be user-provided for prototypical purposes.
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; Implementation by John Metcalf of
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; http://www.retroprogramming.com/2017/07/xorshift-pseudorandom-numbers-in-z80.html
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; (Slightly altered for CollapseOS)
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;
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; 16-bit xorshift pseudorandom number generator
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;
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; in: hl = seed
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; out: hl = pseudorandom number (generally fed into the next call)
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; corrupts a
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rnd:
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ld a,h
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rra
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ld a,l
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rra
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xor h
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ld h,a
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ld a,l
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rra
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ld a,h
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rra
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xor l
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ld l,a
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xor h
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ld h,a
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ret |