Routines
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43136: 1UP/ 2UP Swapper
Used by the routines at NewGame and 43189.
This routine "swaps" the data between DE and HL.
These are all the player states.
ChangePlayer 43136 LD HL,24224 HL=ActivePlayer_Level.
43139 LD DE,24228 DE=InactivePlayer_Level.
43142 LD B,4 B=4 (counter).
This looks complicated but it's just grabbing the data from DE, grabbing the data from HL, and writing the others data to each one.
ChangePlayer_States 43144 LD A,(DE) A=fetch byte from DE.
43145 LD C,(HL) C=fetch byte from HL.
43146 LD (HL),A Write the byte from DE to HL, and the byte from HL to DE.
43147 LD A,C
43148 LD (DE),A
43149 INC HL Increment HL by one.
43150 INC DE Increment DE by one.
43151 DJNZ ChangePlayer_States Decrease counter by one and loop back to ChangePlayer_States until counter is zero.
This is the current terrain buffer data.
43153 LD HL,28672 HL=TerrainData_Active.
43156 LD DE,29696 DE=TerrainData_Inactive.
43159 LD BC,1024 BC=1024 (counter).
43162 CALL ChangePlayer_Loop Call ChangePlayer_Loop.
And this is the active sprites.
43165 LD HL,24720 HL=24720.
43168 LD DE,25152 DE=25152.
43171 LD BC,288 BC=288 (counter).
This is identical to the copier routine above, except it uses BC for the counter and not only B.
ChangePlayer_Loop 43174 PUSH BC Stash BC on the stack.
43175 LD A,(DE) A=fetch byte from DE.
43176 LD C,(HL) C=fetch byte from HL.
43177 LD (HL),A Write the byte from DE to HL, and the byte from HL to DE.
43178 LD A,C
43179 LD (DE),A
43180 INC HL Increment HL by one.
43181 INC DE Increment DE by one.
43182 POP BC Restore BC from the stack.
43183 DEC BC Decrease BC by one.
43184 LD A,B Jump back to ChangePlayer_Loop until BC is zero.
43185 OR C
43186 JR NZ,ChangePlayer_Loop
43188 RET Return.
View the equivalent code in;
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