Hello,


I hope I'm in the right place. I want some help to design a circuit
converts four analogue variables (-12v to + 12 v) into digital signals
and send it to computer. There are another 10 variables but they are
only ON/OFF. The voltage for them will be 12v when they are ON and 0
when they OFF, so they need to be converted into 1 and 0 in order to be
sent to the computer. I want to know:

1- Is it possible to connect all of these variables to the computer at
the same time?
2- What components do I need?
3- What is the best way to have the most accurate results?
4- Which port will be used?
5- What is the best way to display the results on the computer?

thank u