Routines
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A51D: Pseudo-random number generator
Seed from $A23A, $A23B and $A23C. Used by the routines at 9683, 99E3, 9BA7, 9E67, BC48, BEAD, BEF1, BF95, BFA8, C059, C598, C5A7, C5B4, C5BE, C5E8 and CA69.
Output
A Pseudo-random number
A51D PUSH HL
A51E LD A,($A23A)
A521 SLA A
A523 SLA A
A525 LD HL,$A23A
A528 ADD A,(HL)
A529 ADD A,$15
A52B LD ($A23A),A
A52E POP HL
A52F RET
Used by the routines at 99E3, 9BA7, 9F15, A023, BEF1, CA69 and CC75.
A530 PUSH HL
A531 LD ($A22C),BC
A535 LD B,$08
A537 LD A,($A23A)
A53A AND $48
A53C ADC A,$38
A53E RLA
A53F RLA
A540 LD HL,$A23C
A543 RL (HL)
A545 DEC HL
A546 RL (HL)
A548 DEC HL
A549 RL (HL)
A54B DJNZ $A537
A54D LD A,($A23A)
A550 LD BC,($A22C)
A554 POP HL
A555 RET
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