Protoboard activity: Design a 2-bit counter, with one input M, using J-K flip-flops. • If M=0, the counter performs binary down counting 00à11à10à01à00 • If M=1, the counter performs Gray counting 00à01à11à10à00. Display the output. Hint: Use the 7 segment display/driver board for the display, switch for M, and the timer board to generate clock signal with 1Hz. Some general suggestions: • Use LogicWorks to develop the circuit. Record the pin numbers of the chips you use. • Check and verify as you build. • Have the non-builder check wiring. Extra wires are harder to find than missing wires. • Check all power and ground connections. • Use a "Divide and Conquer": Start with what you know is working, such as the input, and independently test the output or other sections. • Use the logic probe to see what you have.

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