| Routines

F8F6: Check whether MR CREAK can reveal his safe combination letter

Used by the routine at F6D7. Returns with the carry flag reset if we're dealing with MR CREAK and ERIC has not yet opened the safe.
Input
H | Teacher's character number (0xA3-0xA6)
F8F6 | LD BC,$F1C1 | Prepare BC (F1C1='SILENCE! OR I'LL CANE THE LOT OF YOU') before returning
F8F9 | LD A,H | A=teacher's character number
F8FA | CP $A6 | Return with the carry flag set if it's not MR CREAK (0xA6)
F8FC | RET C
F8FD | LD A,($7FEA) | Collect the game mode indicator from 7FEA
F900 | DEC A | Set the carry flag if it's demo mode or ERIC has already opened the safe
F901 | CP $02
F903 | CCF
F904 | RET |