Understanding Digital Design The Random Number Generator Digital

Random Number Generator Digital Design - Demo This presentation will • Review the Board Game Counter block diagram. • Review the circuit design of the sequential logic section of the Board Game Counter. • Review the circuit design of the combinational logic section of the Board Game Counter. 2

Random Number Generator Block Diagram A Analog Section CLOCK Sequential Logic Section 0 0 0 1 1 1 B 0 1 1 0 0 1 C 1 0 1 0 Combinational Logic Section L 1 L 2 L 3 L 4 L 5 L 6 L 7 1 2 3 4 5 6 The Analog Section produces a dampened square wave that “rolls” the count and slowly stops. On every pulse of the clock, the Sequential Logic Section increments a binary count from 1 to 6, then repeats. The Combinational Logic Section encodes the binary count into the die’s seven dots. 3

Random Number Generator Block Diagram A Analog Section CLOCK The Analog Section produces a dampened square wave that “rolls” the count and slowly stops. Sequential Logic Section B C On every pulse of the clock, the Sequential Logic Section increments a binary count from 1 to 6, then repeats. Combinational Logic Section L 1 L 2 L 3 L 4 L 5 L 6 L 7 The Combinational Logic Section encodes the binary count into the die’s seven dots. 4

Sequential Logic Section Schematic Diagram 3 -Bit Counter Default Count Range (010 = 0002 to 710 = 1112) A B C CLOCK Set / Reset Logic Sequential Logic Section Changes Count Range (110 = 0012 to 610 = 1102) 5

Sequential Logic Section Functional Test (1 of 6) Count of “ 1” (A=0; B=0; C=1) CLOCK Logic ‘ 1’ Logic ‘ 0’ 6

Sequential Logic Section Functional Test (2 of 6) Count of “ 2” (A=0; B=1; C=0) CLOCK Logic ‘ 1’ Logic ‘ 0’ 7

Sequential Logic Section Functional Test (3 of 6) Count of “ 3” (A=0; B=1; C=1) CLOCK Logic ‘ 1’ Logic ‘ 0’ 8

Sequential Logic Section Functional Test (4 of 6) Count of “ 4” (A=1; B=0; C=0) CLOCK Logic ‘ 1’ Logic ‘ 0’ 9

Sequential Logic Section Functional Test (5 of 6) Count of “ 5” (A=1; B=0; C=1) CLOCK Logic ‘ 1’ Logic ‘ 0’ 10

Sequential Logic Section Functional Test (6 of 6) Count of “ 6” (A=1; B=1; C=0) CLOCK Logic ‘ 1’ Logic ‘ 0’ 11

Random Number Generator Block Diagram A Analog Section CLOCK The Analog Section produces a dampened square wave that “rolls” the count and slowly stops. Sequential Logic Section B C On every pulse of the clock, the Sequential Logic Section increments a binary count from 1 to 6, then repeats. Combinational Logic Section L 1 L 2 L 3 L 4 L 5 L 6 L 7 The Combinational Logic Section encodes the binary count into the die’s seven dots. 12

Combinational Logic Section Schematic Diagram A B C Combinational Logic Section Note: Because L 1 / L 5, L 2 / L 6, & L 3 / L 7 are always on together, only one combinational logic circuit was required for each pair. 13

Combinational Logic Section A B C L 1 L 2 L 3 L 4 L 5 L 6 L 7 0 0 0 - - - - 0 0 1 0 0 0 1 1 1 0 0 1 0 1 1 1 0 1 1 1 - - - - Truth Table “ 1” “ 2” “ 3” “ 4” “ 5” “ 6” 14

Combinational Logic Section A B C L 1 L 2 L 3 L 4 L 5 L 6 L 7 0 0 0 - - - - 0 0 1 0 0 0 1 1 1 0 0 1 0 1 1 1 0 1 1 1 - - - - Truth Table Again, note that L 1 / L 5, L 2 / L 6, & L 3 / L 7 have the same entries in the truth table; therefore, they are equal functions. 15

Combinational Logic Section Functional Test (1 of 6) Count of “ 1” (A=0; B=0; C=1) A=0 B=0 C=1 Logic ‘ 1’ Logic ‘ 0’ 16

Combinational Logic Section Functional Test (2 of 6) Count of “ 2” (A=0; B=1; C=0) A=0 B=1 C=0 Logic ‘ 1’ Logic ‘ 0’ 17

Combinational Logic Section Functional Test (3 of 6) Count of “ 3” (A=0; B=1; C=1) A=0 B=1 C=1 Logic ‘ 1’ Logic ‘ 0’ 18

Combinational Logic Section Functional Test (4 of 6) Count of “ 4” (A=1; B=0; C=0) A=1 B=0 C=0 Logic ‘ 1’ Logic ‘ 0’ 19

Combinational Logic Section Functional Test (5 of 6) Count of “ 5” (A=1; B=0; C=1) A=1 B=0 C=1 Logic ‘ 1’ Logic ‘ 0’ 20

Combinational Logic Section Functional Test (6 of 6) Count of “ 6” (A=1; B=1; C=0) A=1 B=1 C=0 Logic ‘ 1’ Logic ‘ 0’ 21

Combinational Logic Section Using LEDs LED – Light Emitting Diode A=1 B=0 C=0 Shown with a count of “ 4” (A=1; B=0; C=0) 22

Analog Section Random Number Generator Digital Section Sequential Logic Section Combinational Logic Section Discussed in the previous lesson 23