Oliver,
The best thing to do is show us where you have got to.

What ports do you want to use ? What processor ?

In the general case, this IS pretty easy.

You are just building a CASE statement really.
<pre>
MOV A,P1
MOV P0,#0;
DEC A
JNZ step1
SETB P0.0
step1: DEC A
JNZ step2
SETB P0.1
step2: DEC A
JNZ step3
SETB P0.2
step3: ;etc

Is one method, but suffers from obvious problems.The better method needs a 16 byte look up table to do a generic portaddressing.
Look at the MOVC A,@DPTR + A instruction for ideas.

Steve


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