[supercat]

Well, it's not like anyone else will...

I just downloaded Turbo Pascal 3.0 for CP/M awhile ago to see if it would be usable for a Z80 project I'm working on. If ByteVar is a byte variable, depending upon whether the value in HL is needed, optimal code for "ByteVar:=ByteVar+1;" is either:

LD HL,ByteVar
INC (HL)

or

LD A,(ByteVar)
INC A
LD (ByteVar),A

Unfortunately, Turbo Pascal isn't quite so efficient:

LD HL,(ByteVar)
LD H,0
PUSH HL
LD HL,1
POP DE
ADD HL,DE
LD A,L
LD (ByteVar),A

I think I'll try looking at Turbo Pascal 3.0 for PC's code and see how that is. Many applications were developed on that platform, including the original Tetris.

[DB]

You also need to look at the cycle count for the different ways of doing it (the first two ways…) to see which is really the most efficient time wise (if you care).