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; returns h * l in hl
HtimesL:
push de
ld a, h
ld e, l
ld d, $0
ld l, d
ld h, d
jr .asm_887
.asm_882
add hl, de
.asm_883
sla e
rl d
.asm_887
srl a
jr c, .asm_882
jr nz, .asm_883
pop de
ret
; return a random number between 0 and a (exclusive) in a
Random:
push hl
ld h, a
call UpdateRNGSources
ld l, a
call HtimesL
ld a, h
pop hl
ret
; get the next random numbers of the wRNG1 and wRNG2 sequences
UpdateRNGSources:
push hl
push de
ld hl, wRNG1
ld a, [hli]
ld d, [hl] ; wRNG2
inc hl
ld e, a
ld a, d
rlca
rlca
xor e
rra
push af
ld a, d
xor e
ld d, a
ld a, [hl] ; wRNGCounter
xor e
ld e, a
pop af
rl e
rl d
ld a, d
xor e
inc [hl] ; wRNGCounter
dec hl
ld [hl], d ; wRNG2
dec hl
ld [hl], e ; wRNG1
pop de
pop hl
ret
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