Below on the left is the logic symbol for a 4:1 Multiplexer (MUX). You can copy...

  

 

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Below on the left is the logic symbol for a 4:1 Multiplexer (MUX). You can copy this symbol to make logic diagram later in the lab 2 report. On the right is the 4:1 MUX IC diagram (on second page of ic_diagrams.pdf). Two 4:1 Multiplexers D3:0: S1:0: Y: Gb: DO 1G 10 16- VDD data S1 2 15 - 2G select D1 1D3 -3 so 14E Y 1D2 output enable 4 13 2D3 D2 1D1 2D2 always @ (1Gb, s, 1D) if (1Gb) 1Y = 0; 1Y = 1D[S); always @ (2Gb, s, 2D) if (2Gb) 2Y = 0; 2Y = 2D[S]; 12 D3 1D0 2D1 11 else 1Y 10 2D0 else GND -8 9- 2Y S1 1 So so 74153 4:1 Mux On the right of the IC diagram we have a piece of Verilog code that describes how the MUX works. Read the code and answer the following questions: - How many select bits we have in a 4:1 Mux? Which select bit is the most significant bit? Suppose S1 = 1, so = 0 and 1G = 0, then which signal will be assigned to output 1Y? Now we still have S1 = 1, SO = 0 but 1G = 1, then what will 1Y be? Notice that we also have another set of inputs 2D and output 2Y. Explain how 2Y is related to 2D in one or two sentences. Q2: Below on the left is the logic symbol for a 4:16 Decoder, on the right is the circuit diagram (taken from DECODER_75154.pdf) INPUTS OUTPUTS A B D G2 G1 15 14 13 12 11 1 24 23 22 21 20 19 18 17 16 15 14 13 A 4 B 6. 7 8 9 10 D 11 12 13 3 5 6 7 9 10 11 12 14 1 3 4 6 8 9 10 GND 15 G1 OUTPUTS G2 In DECODER_75154.pdf, on the second page you will see a Function Table for the decoder IC. Note that H = High Level or logic value 1, L = Low Level or logic value 0, X = don't care. Answer the following questions: Given G1 and G2 are two enable pins. For the decoder to function, which logic value should we assign to G1 and G2? In a decoder, basically we select one output (among all outputs) based on the inputs. Suppose we set the enable pins correctly, and we set A = 0, B = 1, C = 0, D = 1, which output is chosen? The chosen output is high or low? Now think again about the inputs that we have. Given that the output number indicates the decimal value of the inputs, which input (A or B or C or D) should be considered the most significant bit? Which should be the least significant bit? Below on the left is the logic symbol for a 4:1 Multiplexer (MUX). You can copy this symbol to make logic diagram later in the lab 2 report. On the right is the 4:1 MUX IC diagram (on second page of ic_diagrams.pdf). Two 4:1 Multiplexers D3:0: S1:0: Y: Gb: DO 1G 10 16- VDD data S1 2 15 - 2G select D1 1D3 -3 so 14E Y 1D2 output enable 4 13 2D3 D2 1D1 2D2 always @ (1Gb, s, 1D) if (1Gb) 1Y = 0; 1Y = 1D[S); always @ (2Gb, s, 2D) if (2Gb) 2Y = 0; 2Y = 2D[S]; 12 D3 1D0 2D1 11 else 1Y 10 2D0 else GND -8 9- 2Y S1 1 So so 74153 4:1 Mux On the right of the IC diagram we have a piece of Verilog code that describes how the MUX works. Read the code and answer the following questions: - How many select bits we have in a 4:1 Mux? Which select bit is the most significant bit? Suppose S1 = 1, so = 0 and 1G = 0, then which signal will be assigned to output 1Y? Now we still have S1 = 1, SO = 0 but 1G = 1, then what will 1Y be? Notice that we also have another set of inputs 2D and output 2Y. Explain how 2Y is related to 2D in one or two sentences. Q2: Below on the left is the logic symbol for a 4:16 Decoder, on the right is the circuit diagram (taken from DECODER_75154.pdf) INPUTS OUTPUTS A B D G2 G1 15 14 13 12 11 1 24 23 22 21 20 19 18 17 16 15 14 13 A 4 B 6. 7 8 9 10 D 11 12 13 3 5 6 7 9 10 11 12 14 1 3 4 6 8 9 10 GND 15 G1 OUTPUTS G2 In DECODER_75154.pdf, on the second page you will see a Function Table for the decoder IC. Note that H = High Level or logic value 1, L = Low Level or logic value 0, X = don't care. Answer the following questions: Given G1 and G2 are two enable pins. For the decoder to function, which logic value should we assign to G1 and G2? In a decoder, basically we select one output (among all outputs) based on the inputs. Suppose we set the enable pins correctly, and we set A = 0, B = 1, C = 0, D = 1, which output is chosen? The chosen output is high or low? Now think again about the inputs that we have. Given that the output number indicates the decimal value of the inputs, which input (A or B or C or D) should be considered the most significant bit? Which should be the least significant bit?