| Routines

64599: Hide the play area

Used by the routines at 30822 and 64338. Hides the play area and clears the screen refresh buffer (SRB).
64599 | LD HL,23167 | Set the attribute bytes for the top 20 rows of the screen to 9 (INK 1: PAPER 1)
64602 | LD (HL),9
64604 | DEC HL
64605 | BIT 3,H
64607 | JR NZ,64602
64609 | LD HL,32607 | Set every byte in the SRB to 0
64612 | LD (HL),0
64614 | DEC L
64615 | JR NZ,64612
64617 | RET |