| Routines

F17F: Get a random number

Used by the routines at 61CF, 621E, 62DB, 634C, 6670, 6FC8, 72B1, 77A3, 7996, 7B6A, F485, F6E9, F748, F82A, FA05 and FB52. Returns with a random number in A.
F17F | PUSH HL |
F180 | LD HL,($7FDE) | Collect the random number seed from 7FDE
F183 | INC HL | Add 257 to it
F184 | INC H
F185 | LD ($7FDE),HL | Store the new seed
F188 | LD A,($5C78) | Collect the LSB of the system variable FRAMES, which is incremented every 20ms
F18B | XOR (HL) | A=random number
F18C | POP HL |
F18D | RET |