U3L2SSIsynchronousModuluscounters

In the assignment, we saw how easy it was to design asynchronous counters using either the D or J/K flip-flop. These designs had two big limitations. First, the count limit had to be a power of two (e.g., 2, 4, 8, 16, 32, etc.). All counts also started or ended at a count of zero. In the real world, we frequently need to set the count limit to some arbitrary value (10, 25, 85, etc.). More often than not, the starting or ending value will not be zero. For this reason we must design asynchronous modulus counters. An asynchronous modulus counter, or mod-counter, uses the addition of simple combinational logic to a standard asynchronous counter to set the count limit and starting point. In this activity we will simulate and build a Mod-5 counter that has a starting count of one.
Integraded circuits used:
74LC74 74LS10 74LS47 74LS48

The circuit shown below is a 3-Bit Mod-6 Up Counter implemented with 74LS74 D flip-flops. In this design the count will be displayed on a common anode seven-segment display using a 74LS47 encoder. This design will count from 0 to 5 and then repeat.

3-Bit Mod-6 Up Counter with D Flip-Flops

a. Use Multisim to enter the 3-Bit Mod-6 Up Counter. Add a four-channel oscilloscope to monitor the signals Q₀, Q₁, Q_2, and the output of the NAND gate. Run the simulation and capture a full count cycle (0-5) of the signal. Verify that the circuit is working as expected. If the results are not what are expected, review your circuit and make any necessary corrections. SHOW ME YOUR WORKING CIRCUIT!

b. Adjust the time-base of the oscilloscope to zoom into the point in time that the counter is changing from a count of 5 (101) to 0 (000). Show me your waveforms.

c. Make the necessary modification to this circuit to change the count to 2 (010) to 6 (110). This is now a Mod-7 Up Counter with a start of 2 (010). Run the simulation and verify that the circuit is working as expected. If not, review your circuit, make any necessary corrections, and retest. Use a 74LS48 and a common cathode seven-segment display for this simulation in preparation for the next problem. SHOW ME YOUR WORKING CIRCUIT!

Problem
	1.	In the assignment, we saw how easy it was to design asynchronous counters using either the D or J/K flip-flop. These designs had two big limitations. First, the count limit had to be a power of two (e.g., 2, 4, 8, 16, 32, etc.). All counts also started or ended at a count of zero. In the real world, we frequently need to set the count limit to some arbitrary value (10, 25, 85, etc.). More often than not, the starting or ending value will not be zero. For this reason we must design asynchronous modulus counters. An asynchronous modulus counter, or mod-counter, uses the addition of simple combinational logic to a standard asynchronous counter to set the count limit and starting point. In this activity we will simulate and build a Mod-5 counter that has a starting count of one. Integraded circuits used: 74LC74 74LS10 74LS47 74LS48 The circuit shown below is a 3-Bit Mod-6 Up Counter implemented with 74LS74 D flip-flops. In this design the count will be displayed on a common anode seven-segment display using a 74LS47 encoder. This design will count from 0 to 5 and then repeat. 3-Bit Mod-6 Up Counter with D Flip-Flops a. Use Multisim to enter the 3-Bit Mod-6 Up Counter. Add a four-channel oscilloscope to monitor the signals Q₀, Q₁, Q_2, and the output of the NAND gate. Run the simulation and capture a full count cycle (0-5) of the signal. Verify that the circuit is working as expected. If the results are not what are expected, review your circuit and make any necessary corrections. SHOW ME YOUR WORKING CIRCUIT! b. Adjust the time-base of the oscilloscope to zoom into the point in time that the counter is changing from a count of 5 (101) to 0 (000). Show me your waveforms. c. Make the necessary modification to this circuit to change the count to 2 (010) to 6 (110). This is now a Mod-7 Up Counter with a start of 2 (010). Run the simulation and verify that the circuit is working as expected. If not, review your circuit, make any necessary corrections, and retest. Use a 74LS48 and a common cathode seven-segment display for this simulation in preparation for the next problem. SHOW ME YOUR WORKING CIRCUIT!
	2.	Breadboard the 2-to-6 count Mod-7 counter. Show me your working breadboarded circuit when you are finished.
	3.	If time permits, program the FPGA board to display the 2-to-6 counter. Show me your working board.