Routines
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65D6: Generate Random Number
Used by the routines at GameLoop and ActionKill.
Return a number derived from the frame counter, used when an event may or may not happen.
Output
A A random number derived from *FRAMES
GenerateRandomNumber 65D6 PUSH BC Take the frame counter as a countdown, limited by the value passed in.
65D7 LD C,A
65D8 LD A,($5C78)
65DB LD B,A
65DC LD A,C
GenerateRandomNumber_Loop1 65DD DEC A Wrap back to that limit when the countdown passes zero.
65DE JR NZ,GenerateRandomNumber_Step1
65E0 LD A,C
GenerateRandomNumber_Step1 65E1 DJNZ GenerateRandomNumber_Loop1 Repeat for every frame that has passed.
65E3 DEC A Step the result back one more.
65E4 POP BC Restore the registers the caller needs from the stack.
65E5 RET Return.
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