| Routines

F9FA: Initialise an uninterruptible subcommand

Used by the routine at FA83. Places the return address into bytes 0x12 and 0x13 of the character's buffer, thus making it the address of the character's uninterruptible subcommand routine.
Input
H | Character number (0xD7-0xE5)
F9FA | POP BC | Drop the return address from the stack into BC
F9FB | PUSH BC | Push the return address back onto the stack
F9FC | PUSH BC | Push the return address onto the stack again in preparation for the 'POP BC' below
This entry point is used by the routine at FA05.
F9FD | LD L,$13 | Point HL at byte 0x13 of the character's buffer
F9FF | POP BC | Drop the return address from the stack into BC
FA00 | LD (HL),B | Copy the address from BC into bytes 0x12 and 0x13 of the character's buffer, thus setting his uninterruptible subcommand
FA01 | DEC L
FA02 | LD (HL),C
FA03 | RET |