1.0 Two bit binary adder
1.1 Assemble the two bit binary adder that you have designed from logic gates in the prelab exercises on the digital experimenter available in the lab.
1.2 Apply the necessary input combinations to test your circuit. You'll be using the switches on the digital experimenter as your data inputs. Connect the SUM and CARRY outputs to the LEDs on the experimenter for observations.
1.3 Record all your observations in the log book.
1.4 If
there is any error in your results, troubleshoot your circuit. Or else
get your lab demonstrator's approval that your circuit is functioning.
2.0 Addition Using 4 bit Full Adder From 74LS83
2.1 Place the 74LS83 full adder IC on the experimenter board.
2.2 Apply the numbers for addition in the prelab exercise 2.1 to the adder to test the circuit. These input combinations are called test vectors. Normally for a large circuit it is not possible to apply all input combinations to test the circuit. Therefore, a set of appropriate test vectors are needed in order to test and verify the circuit's functionality.
2.3 Record all your observations in the log book.
2.4 Compare
your lab results to those that you have obtained in the prelab exercises.
If there is any error in your results, troubleshoot your circuit. Or else
get your lab demonstrator's approval that your circuit is functioning.
3.0 Subtraction Using 4 bit Full Adder from 74LS83.
3.1 Place the 74LS83 full adder IC on the experimenter board.
3.2 Set C0 = 1.
3.3 Note that you will also need to invert the subtrahend before connecting it to the 74LS83 adder inputs. Use 74LS04 inverter IC to perform the inversion.
3.4 Apply the numbers for subtraction as in the prelab exercise 3.1 to the circuit to test the subtract function of the circuit.
3.5 Record all your observations in the log book.
3.6 Compare
your lab results to those that you have obtained in the prelab exercises.
If there is any error in your results, troubleshoot your circuit. Or else
get your lab demonstrator's approval that your circuit is functioning.