Routines
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C47E: Initialise Special Objects
Used by the routine at InitialiseGame.
Chooses the objects in SpecialObjectsTable at the start of a game. Each is given a graphic number from 60 to 67 taken from a number made from the random number seed and the refresh register. The starting position of each entry is copied to the current position.
Stir the seed and fill the table.
InitialiseSpecialObjects C47E LD HL,$6FF2 Point HL at the first special object, SpecialObjectsTable.
C481 LD A,($5BA0) Fetch the first random seed from RandomSeed1.
C484 LD E,A Keep it in E.
C485 LD A,R Fetch the refresh register.
C487 ADD A,E Add the seed to it.
C488 LD E,A Keep the result in E.
InitialiseSpecialObjects_Next C489 LD A,E Copy the number to A.
C48A AND %00000111 Keep bits 0 to 2.
C48C OR %01100000 Make it a graphic number from 60 to 67.
C48E LD (HL),A Set the graphic number of the object.
C48F INC HL Move on to the starting position.
C490 INC E Change the number, for the next object.
C491 PUSH DE Stash the number on the stack.
C492 EX DE,HL Swap the entry pointer into DE.
C493 LD HL,$0004 Set HL to 0004.
C496 ADD HL,DE Add it to the starting position.
C497 EX DE,HL Swap the pointers back.
C498 LD BC,$0004 Set BC to 0004.
C49B LDIR Copy the starting position and room.
C49D EX DE,HL Point HL at the next object.
C49E PUSH HL Stash the next entry on the stack.
C49F LD BC,$7112 Point BC at SpriteTable.
C4A2 AND A Subtract SpriteTable from HL.
C4A3 SBC HL,BC
C4A5 POP HL Restore the address of the next object from the stack.
C4A6 POP DE Restore the number from the stack.
C4A7 JR C,InitialiseSpecialObjects_Next Jump to InitialiseSpecialObjects_Next until every object has been done.
C4A9 RET Return.
View the equivalent code in;
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