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Lab #2 Activity Build the given circuit used to display numbers using a 7-segment display. The schematics on the following pages show the circuit using a common anode (CA) 7-segment display (M72) using the 74LS47 BCD to 7-segment active low decoder and the common cathode (CC) 7-segment display (M74) with the 74LS48 BCD to 7-segment active high decoder. 1) Select one of the designs (CA or CC) CA CC 2) Use the necessary datasheets 3) Show your instructor a schematic of your design (complete schematic showing all the signals, name of signals, and pin numbers). 4) Simulate the circuit and show instructor the simulation result. 5) Build the circuit and show your instructor the working circuit. Do not take the circuit apart as it is used in lab activity #3! 3
Lab #2 Activity A0 A1 A2 A3 (A0 A3 signals are generated by using 4 Switches located on the digital module card) 74LS47 BCD To 7-seg Decoder active Low outputs a g CA 7-segment display +5v R 470Ω Common Anode 7-segment display design 4
Lab #2 Activity A0 A1 A2 A3 (A0 A3 signals are generated by using 4 Switches located on the digital module card) 74LS48 BCD To 7-seg Decoder active High outputs a g CC 7-segment display Ground R 470Ω Common Cathode 7-segment display design 5
Lab #2 Activity 6
Lab #2 Activity 74LS47 Connection Data 74LS47 7
Lab #2 Activity 74LS47 Truth Table 8
Lab #2 Activity Common Anode: M72 9
Lab #2 Activity Common Cathode: M74 10
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Lab #3 Activity Build a circuit that will add two 4-bit binary numbers (A0 A3 and B0 B3). Use the 74LS83 full adder chip to perform this 4-bit addition. Display the sum value using the common anode 7-segment display or the common cathode display (M74 C/D) built in lab activity #2. As well, display the carry bit. A block diagram of this circuit is shown on the next two pages. 1) Show your instructor a schematic of your design (complete schematic showing all the signals, name of signals, and pin numbers). 4) Simulate the circuit and show instructor the simulation result. 5) Build the circuit and show your instructor the working circuit. Do not take the circuit apart as it is used in lab activity #4! 12
Lab #3 Activity S 0 S 3 74ls83 4-bit Full Adder Cin GND A D BCD To 7-seg decoder 74LS47 a g CA 7-segment display Cout R 470 Ohms A3 A2 A1A0 B3 B2 B1 B0 Switches Carry bit LED +5 v (Digital Module) Common Anode 7-segment display design 13
Lab #3 Activity S 0 S 3 74ls83 4-bit Full Adder Cin GND A D BCD To 7-seg decoder 74LS48 a g CC 7-segment display Cout R 470 Ohms A3 A2 A1A0 B3 B2 B1 B0 Switches Carry bit LED Gnd (Digital Module) Common Cathode 7-segment display design 14
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Lab #4 Activity Build a circuit that will add and subtract two 4-bit binary numbers (A0 A3 and B0 B3). Use the 74LS83 full adder circuit, (used in lab activity #3), and add XOR gates to perform the 4-bit addition & subtraction. Display the sum value using the common anode 7-segment display or the common cathode display (M74 C/D) used in lab activity #3. A block diagram of this circuit is shown on the next two pages. 1) Show your instructor a schematic of your design (complete schematic showing all the signals, name of signals, and pin numbers). 4) Simulate the circuit and show instructor the simulation result. 5) Build the circuit and show your instructor the working circuit. Do not take the circuit apart as it is used in lab activity #5! 16
Lab #4 Activity 2 s Complement Adder &Subtract circuit To 7-segment display circuit from lab activity #3 74ls86 Carry bit LED 17 17
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Lab #5 Activity Build a circuit that will compare two 4-bit binary numbers (A0 A3 and B0 B3). Use the 74LS85 comparator chip to perform this 4-bit comparison. Display, using three LEDs, whether A = B, A > B or A < B. Use the adder circuit and the common anode 7-segment display or the common cathode display (M74 C/D) used in lab activity #4. A block diagram of this circuit is shown on the next two pages. 1) Show your instructor a schematic of your design (complete schematic showing all the signals, name of signals, and pin numbers). 4) Simulate the circuit and show instructor the simulation result. 5) Build the circuit and show your instructor the working circuit. 19
Lab #5 Activity S 0 S 3 74ls83 4-bit Full Adder Cin Cout A D + BCD To 7-seg decoder 74LS47 a g CA 7-segment display LED R 470 Ohms 74ls86 A3 A2 A1A0 B3 B2 B1 B0 Switches (Digital Module) Common Anode 7-segment display design 74ls85 4-bit Comparator A<B A>B A=B +5v 20
Lab #5 Activity S 0 S 3 74ls83 4-bit Full Adder Cin Cout GND A D BCD To 7-seg decoder 74LS48 a g CC 7-segment display R 470 Ohms 74ls86 A3 A2 A1A0 B3 B2 B1 B0 Switches (Digital Module) Carry bit LED Common Cathode 7-segment display design 74ls85 4-bit Comparator A<B A>B A=B Gnd 21