Why do you want to make an I/O table?
If you are using standard I/O cards then;
Inputs start at word 0, outputs at word 100.
The first input is 0.00 then 0.01 up to 0.15 then the next input is 1.00
The first output is 100.00 then 100.01 up to 100.15 then the next output is 100.00
If you are using other types of cards it can get more complex, you need to post a list of cards for help with this.