sol8 - Chapter 8 8.1. The expressions for the inputs of the...

Info iconThis preview shows pages 1–6. Sign up to view the full content.

View Full Document Right Arrow Icon
Chapter 8 8.1. The expressions for the inputs of the Fip-Fops are D 2 = Y 2 = wy 2 + y 1 y 2 D 1 = Y 1 = w y 1 y 2 The output equation is z = y 1 y 2 8.2. The excitation table for JK Fip-Fops is Present ±lip-Fop inputs state w = 0 w = 1 Output y 2 y 1 J 2 K 2 J 1 K 1 J 2 K 2 J 1 K 1 z 00 1 d 0 d 1 d 1 d 0 01 0 d d 0 0 d d 1 0 10 d 0 1 d d 1 0 d 0 11 d 0 d 1 d 1 d 0 1 The expressions for the inputs of the Fip-Fops are J 2 = y 1 K 2 = w J 1 = wy 2 + w y 2 K 1 = J 1 The output equation is z = y 1 y 2 8.3. A possible state table is Present Next state Output z state w = 0 w = 1 w = 0 w = 1 A A B 0 0 B E C 0 0 C E D 0 0 D E D 0 1 E ± B 0 0 ± A B 0 1 8-1
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
8.4. Verilog code for the solution given in problem 8.3 is module prob8 4 (Clock, Resetn, w, z); input Clock, Resetn, w; output z; reg z; reg [3:1] y, Y; parameter [3:1] A = 3’b000, B = 3’b001, C = 3’b010, D = 3’b011, E = 3’b100, F = 3’b101; // De±ne the next state and output combinational circuits always @(w or y) case (y) A: if (w) begin Y = B; z = 0; end else begin Y = A; z = 0; end B: if (w) begin Y = C; z = 0; end else begin Y = E; z = 0; end C: if (w) begin Y = D; z = 0; end else begin Y = E; z = 0; end D: if (w) begin Y = D; z = 1; end else begin Y = E; z = 0; end E: if (w) begin Y = B; z = 0; end else begin Y = F; z = 0; end F: if (w) begin Y = B; z = 1; end else begin Y = A; z = 0; end default: begin Y = 3’bxxx; z = 0; end endcase 8-2
Background image of page 2
// Defne the sequential block always @( negedge Resetn or posedge Clock) if (Resetn == 0) y < = A; else y < = Y; endmodule 8.5. A minimal state table is Present Next State Output state w = 0 w = 1 z A A B 0 B E C 0 C D C 0 D A F 1 E A F 0 F E C 1 8.6. An initial attempt at deriving a state table may be Present Next state Output z state w = 0 w = 1 w = 0 w = 1 A A B 0 0 B D C 0 0 C D C 1 0 D A E 0 1 E D C 0 0 States B and E are equivalent; hence the minimal state table is Present Next state Output z state w = 0 w = 1 w = 0 w = 1 A A B 0 0 B D C 0 0 C D C 1 0 D A B 0 1 8-3
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
8.7. For Figure 8.51 have (using the straightforward state assignment): Present Next state state w = 0 w = 1 Output y 3 y 2 y 1 Y 3 Y 2 Y 1 Y 3 Y 2 Y 1 z A 0 0 0 0 0 1 0 1 0 1 B 0 0 1 0 1 1 1 0 1 1 C 0 1 0 1 0 1 1 0 0 0 D 0 1 1 0 0 1 1 1 0 1 E 1 0 0 1 0 1 0 1 0 0 F 1 0 1 1 0 0 0 1 1 0 G 1 1 0 1 0 1 1 1 0 0 This leads to Y 3 = wy 3 + y 1 y 2 + wy 1 y 3 Y 2 = wy 3 + w y 1 y 2 + wy 1 y 2 + wy 1 y 2 y 3 Y 1 = y 3 w + y 1 w + wy 1 y 2 z = y 1 y 3 + y 2 y 3 For Figure 8.52 have Present Next state state w = 0 w = 1 Output y 2 y 1 Y 2 Y 1 Y 2 Y 1 z A 0 0 0 1 1 0 1 B 0 1 0 0 1 1 1 C 1 0 1 1 1 0 0 F 1 1 1 0 0 0 0 This leads to Y 2 = wy 2 + y 1 y 2 + w y 2 Y 1 = y 1 w + wy 1 y 2 z = y 2 Clearly, minimizing the number of states leads to a much simpler circuit. 8-4
Background image of page 4
8.8. For Figure 8.55 have (using straightforward state assignment): Present Next state state DN=00 01 10 11 Output y 4 y 3 y 2 y 1 Y 4 Y 3 Y 2 Y 1 z S1 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 1 - 0 S2 0 0 0 1 0 0 0 1 0 0 1 1 0 1 0 0 - 0 S3 0 0 1 0 0 0 1 0 0 1 0 1 0 1 1 0 - 0 S4 0 0 1 1 0 0 0 0 - - - 1 S5 0 1 0 0 0 0 1 0 - - - 1 S6 0 1 0 1
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 6
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 02/16/2011 for the course EE 4745 taught by Professor Rai during the Spring '07 term at LSU.

Page1 / 27

sol8 - Chapter 8 8.1. The expressions for the inputs of the...

This preview shows document pages 1 - 6. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online