Figure 31 Example truth tables for (a) twoinput, (b) threeinput, and (c) fourinput circuits

8/14/2019 Figure3 1Exampletruthtablesfor(a)two input,(b)three input,and(c)four inputcircuits.

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Digital Systems: Principles and Applications, 10eBy Ronald J. Tocci, Neal S. Widmer, and Gregory L. Moss

2007 Pearson Education, Inc.

Pearson Prentice HallUpper Saddle River, NJ 07458

Figure 3-1 Example truth tables for (a) two-input, (b) three-input, and (c) four-input circuits.


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Figure 3-2 (a) Truth table defining the OR operation; (b) circuit symbol for a two-input OR gate.


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Figure 3-3 Symbol and truth table for a three-input OR gate.


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Figure 3-4 Example of the use of an OR gate in an alarm system.


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Figure 3-5 Example 3-2.


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Figure 3-6 Examples 3-3A and B.


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Figure 3-7 (a) Truth table for the AND operation; (b) AND gate symbol.


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Figure 3-8 Truth table and symbol for a three-input AND gate.


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Figure 3-10 Examples 3-5A and B.


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Figure 3-11 (a) Truth table; (b) symbol for the INVERTER (NOT circuit); (c) sample waveforms.


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Figure 3-12 A NOT gate indicating a button is notpressed when its output is true.


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Figure 3-13 (a) Logic circuit with its Boolean expression; (b) logic circuit whose expression requires parentheses.


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Figure 3-13 (continued) (a) Logic circuit with its Boolean expression; (b) logic circuit whose expression requires parentheses.


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Figure 3-14 Circuits using INVERTERs.


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Figure 3-15 More examples.


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Figure 3-16 Analysis of a logic circuit using truth tables.


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Figure 3-17 Constructing a logic circuit from a Boolean expression.


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Figure 3-19 (a) NOR symbol; (b) equivalent circuit; (c) truth table.


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Figure 3-22 (a) NAND symbol; (b) equivalent circuit; (c) truth table.


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Figure 3-24 Examples 3-11 and 3-12.


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Figure 3-25 Single-variable theorems.


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Figure 3-26 (a) Equivalent circuits implied by theorem (16); (b) alternative symbol for the NOR function.


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Figure 3-27 (a) Equivalent circuits implied by theorem (17); (b) alternative symbol for the NAND function.


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Figure 3-29 NAND gates can be used to implement any Boolean function.


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Figure 3-30 NOR gates can be used to implement any Boolean operation.


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Figure 3-31 ICs available for Example 3-18.


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Figure 3-32 Possible implementations for Example 3-18.


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Figure 3-33 Standard and alternate symbols for various logic gates and inverter.


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Figure 3-34 Interpretation of the two NAND gate symbols.


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Figure 3-35 Interpretation of the two OR gate symbols.


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Figure 3-36 (a) Original circuit using standard NAND symbols; (b) equivalent representation where output Z is active-HIGH; (c)

equivalent representation where output Z is active-LOW; (d) truth table.


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Figure 3-41 Standard logic symbols: (a) traditional; (b) IEEE/ANSI.


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Figure 3-42 Methods of describing logic circuits: (a) Boolean expression; (b) schematic diagram; (c) truth table; (d) timing diagram.


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Figure 3-43 Decision process of a computer program.


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Digital Systems: Principles and Applications, 10e

By Ronald J. Tocci, Neal S. Widmer, and Gregory L. Moss


Pearson Prentice Hall

Upper Saddle River, NJ 07458

Figure 3-44 Configuring hardware connections with programmable logic devices.


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Figure 3-45 A schematic diagram description.


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Figure 3-46 Format of HDL files.


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Figure 3-47 Essential elements in AHDL.


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Figure 3-48 Essential elements in VHDL.


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Figure 3-49 A logic circuit diagram with an intermediate variable.

Fi 3 50 I di i bl i AHDL d ib d i Fi 3 49


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Figure 3-50 Intermediate variables in AHDL described in Figure 3-49.

Fi 3 51 I di i l i VHDL d ib d i Fi 3 49


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Figure 3-51 Intermediate signals in VHDL described in Figure 3-49.

Fi 3 52


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Figure 3-52

Fi 3 53


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Figure 3-53

Figure 3 54


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Figure 3-54

Figure 3 55


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Figure 3-55

Figure 3 56


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Figure 3-56

Figure 3-57


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Figure 3-57

Figure 3-58


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Figure 3-58

Documents

Figure 31 Example truth tables for (a) twoinput, (b) threeinput, and (c) fourinput circuits