>>> LDA INPT0 ; read port 0
>>> BMI charged0 ; condenser already charged, skip increment
>>> INC Pot ; increment paddle position value
>>>charged0
>
>(please substitute my "condenser" with "capacitor", btw ;)
If you need to read four paddles, it's faster to do
INC scanline ;not necessary if you already have a scanline variable
LDA scanline
BIT INPT0
BMI charged0
STA Pot0
charged0
BIT INPT1
BMI charged1
STA Pot1
charged1
BIT INPT2
BMI charged2
STA Pot2
charged2
BIT INPT3
BMI charged3
STA Pot3
charged3
this is faster because STA takes two fewer cycles than INC... and it also
leaves you with the scanline in A (or X or Y if you like), saving a load if
you need to use the scanline number again. This way is also less
time-variable - the branches each skip 3 cycles instead of five.
Hey Jim, is there a time-invariant quick way to read all four paddles?
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