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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Digital Fundamentals Tenth Edition Floyd © 2008 Pearson Education Chapter 1
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Most natural quantities that we see are analog and vary continuously. Analog systems can generally handle higher power than digital systems. Digital systems can process, store, and transmit data more efficiently but can only assign discrete values to each point. Analog Quantities
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Many systems use a mix of analog and digital electronics to take advantage of each technology. A typical CD player accepts digital data from the CD drive and converts it to an analog signal for amplification. Analog and Digital Systems
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Shorthand for binary digit, a logic 0 or 1. The most significant bit (MSB) is the leftmost bit of a binary number. The least significant bit (LSB) is the rightmost bit of a binary number. Bit
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Decimal Numbers Express the number 480.52 as the sum of values of each digit. (9 x 10 3 ) + (2 x 10 2 ) + (4 x 10 1 ) + (0 x 10 0 ) or 9 x 1,000 + 2 x 100 + 4 x 10 + 0 x 1 Decimal numbers can be expressed as the sum of the products of each digit times the column value for that digit. Thus, the number 9240 can be expressed as 480.52 = (4 x 10 2 ) + (8 x 10 1 ) + (0 x 10 0 ) + (5 x 10 -1 ) +(2 x 10 -2 )
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Binary Numbers For digital systems, the binary number system is used. Binary has a radix of two and uses the digits 0 and 1 to represent quantities. The column weights of binary numbers are powers of two that increase from right to left beginning with 2 0 =1: …2 5 2 4 2 3 2 2 2 1 2 0. For fractional binary numbers, the column weights are negative powers of two that decrease from left to right: 2 2 2 1 2 0. 2 -1 2 -2 2 -3 2 -4 …
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Hexadecimal Numbers Hexadecimal uses sixteen characters to represent numbers: the numbers 0 through 9 and the alphabetic characters A through F. 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 0123456789ABCDEF0123456789ABCDEF 0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1111 DecimalHexadecimalBinary Large binary number can easily be converted to hexadecimal by grouping bits 4 at a time and writing the equivalent hexadecimal character. Express 1001 0110 0000 1110 2 in hexadecimal: Group the binary number by 4-bits starting from the right. Thus, 960E
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Each hexadecimal digit represents 4 binary bits. 960E 1001 0110 0000 1110 Conversion Between Hexadecimal and Binary
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed BCD Binary coded decimal (BCD) is a weighted code that is commonly used in digital systems when it is necessary to show decimal numbers such as in clock displays. 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1111 DecimalBinaryBCD 0001 0001 0001 0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 0000 0001 0010 0011 0100 0101 The table illustrates the difference between straight binary and BCD. BCD represents each decimal digit with a 4-bit code. Notice that the codes 1010 through 1111 are not used in BCD.
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Gray code Gray code is an unweighted code that has a single bit change between one code word and the next in a sequence. Gray code is used to avoid problems in systems where an error can occur if more than one bit changes at a time. 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1111 DecimalBinaryGray code 0000 0001 0011 0010 0110 0111 0101 0100 1100 1101 1111 1110 1010 1011 1001 1000
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed ASCII ASCII is a code for alphanumeric characters and control characters. In its original form, ASCII encoded 128 characters and symbols using 7-bits. The first 32 characters are control characters, that are based on obsolete teletype requirements, so these characters are generally assigned to other functions in modern usage. In 1981, IBM introduced extended ASCII, which is an 8- bit code and increased the character set to 256. Other extended sets (such as Unicode) have been introduced to handle characters in languages other than English.
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Basic Logic Functions True only if all input conditions are true. True only if one or more input conditions are true. Indicates the opposite condition.
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed A list of output logic levels corresponding to all possible input combinations. The number of input combinations is 2 n, where n is the number of inputs. Truth Table
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed The inverter performs the Boolean NOT operation. When the input is LOW, the output is HIGH; when the input is HIGH, the output is LOW. The Inverter AX LOW (0) HIGH (1) HIGH (1) LOW(0) The NOT operation (complement) is shown with an overbar. Thus, the Boolean expression for an inverter is X = A.
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed The Inverter Example waveforms: A X AX A group of inverters can be used to form the 1’s complement of a binary number: Binary number 1’s complement 1 0 0 0 1 1 0 1 0 1 1 1 0 0 1 0
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed The AND gate produces a HIGH output when all inputs are HIGH; otherwise, the output is LOW. For a 2-input gate, the truth table is The AND Gate The AND operation is usually shown with a dot between the variables but it may be implied (no dot). Thus, the AND operation is written as X = A. B or X = AB. 0 0 1 1 0 1 0 0 0 1 A B X A B X
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed The NAND gate produces a LOW output when all inputs are HIGH; otherwise, the output is HIGH. For a 2-input gate, the truth table is The NAND Gate 0 0 1 1 0 1 1 1 1 0 A B X A B X The NAND operation is shown with a dot between the variables and an overbar covering them. Thus, the NAND operation is written as X = A. B (Alternatively, X = AB.)
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed The OR gate produces a HIGH output if any input is HIGH; if all inputs are LOW, the output is LOW. For a 2-input gate, the truth table is The OR Gate The OR operation is shown with a plus sign (+) between the variables. Thus, the OR operation is written as X = A + B. 0 0 1 1 0 1 0 1 1 1 A B XA B X
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed The NOR gate produces a LOW output if any input is HIGH; if all inputs are HIGH, the output is LOW. For a 2-input gate, the truth table is The NOR Gate 0 0 1 1 0 1 1 0 0 0 A B XA B X The NOR operation is shown with a plus sign (+) between the variables and an overbar covering them. Thus, the NOR operation is written as X = A + B.
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed The XOR gate produces a HIGH output only when both inputs are at opposite logic levels. The truth table is The XOR Gate 0 0 1 1 0 1 0 1 1 0 A B XA B X The XOR operation is written as X = AB + AB. Alternatively, it can be written with a circled plus sign between the variables as X = A + B.
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed The XNOR gate produces a HIGH output only when both inputs are at the same logic level. The truth table is The XNOR Gate 0 0 1 1 0 1 1 0 0 1 A B XA B X The XNOR operation shown as X = AB + AB. Alternatively, the XNOR operation can be shown with a circled dot between the variables. Thus, it can be shown as X = A. B.
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Analog Digital Binary Bit Pulse Being continuous or having continuous values. Related to digits or discrete quantities; having a set of discrete values. Having two values or states; describes a number system that has a base of two and utilizes 1 and 0 as its digits. A binary digit, which can be a 1 or a 0. A sudden change from one level to another, followed after a time, called the pulse width, by a sudden change back to the original level.
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Clock Gate NOT AND OR A basic timing signal in a digital system; a periodic waveform used to synchronize actions. A logic circuit that performs a basic logic operations such as AND or OR. A basic logic function that performs inversion. A basic logic operation in which a true (HIGH) output occurs only when all input conditions are true (HIGH). A basic logic operation in which a true (HIGH) output occurs when when one or more of the input conditions are true (HIGH).
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Inverter Truth table Timing diagram Boolean algebra AND gate A logic circuit that inverts or complements its inputs. A table showing the inputs and corresponding output(s) of a logic circuit. A diagram of waveforms showing the proper time relationship of all of the waveforms. The mathematics of logic circuits. A logic gate that produces a HIGH output only when all of its inputs are HIGH.
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed OR gate NAND gate NOR gate Exclusive-OR gate Exclusive-NOR gate A logic gate that produces a HIGH output when one or more inputs are HIGH. A logic gate that produces a LOW output only when all of its inputs are HIGH. A logic gate that produces a LOW output when one or more inputs are HIGH. A logic gate that produces a HIGH output only when its two inputs are at opposite levels. A logic gate that produces a LOW output only when its two inputs are at opposite levels.
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed 7. AND, OR, and NOT gates can be used to form a. storage devices b. comparators c. data selectors d. all of the above © 2008 Pearson Education
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed 9. A device that is used to switch one of several input lines to a single output line is called a a. comparator b. decoder c. counter d. multiplexer © 2008 Pearson Education
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Chapter 4 Introduction to PLDs and MAX+PLUS II
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Introduction to PLDs 可程式邏輯元件 (PLD, Programmable Logic Device) 即指一種 空白的數位積體電路,可讓使用者自行組成其邏輯功能。 如何使用 PLD ?其實 PLD 的設計很簡單,有數位電路基礎, 會使用 PLD 的研發軟體套件,就可以進行 PLD 的設計。
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Complex PLD (CPLD) A PLD that has several programmable sections with internal interconnections between the sections. In effect, several interconnected PLDs on a single chip.
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed CPLD Design Entry Two general methods. 1. Schematic, or graphic, entry. 2. Text based entry.
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed MAX+PLUS II Graphic Entry Uses a Graphic Design File (.gdf) in which the digital design is entered as a schematic. Shows components and their inter- connections, as well as the input and output names of the circuit. See Figure 4.3
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Creating a Graphic Design File Uses schematic entry. MAX+PLUS II generates other files required for programming. All the files represent a project. See Figure 4.6
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed MAX+PLUS II Project A set of files associated with a particular PLD design. All operations to create program files for a PLD are performed on a project. Always keep track of what the current project is.
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Creating MAX+PLUS II Graphic Design Files First, Save the file to the proper folder. Second, Set Project to Current File. See Figure 4.8
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Entering Components Use cursor to set the component location and press left mouse button. Use right mouse button to enable entry menu. Choose Enter Symbol. See Figure 4.9
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Enter Symbol Menu Allows basic components to be entered by name or selected from a library. Basic components are called primitives. Each copy of a component is called an instance. See Figure 4.10
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Assigning Pin Names Inputs and outputs must be assigned names. Double-click the pin name (e.g. INPUT_VCC) to highlight it and type in the assigned name. See Figure 4.17
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Compiler Processing->Functional
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Hierarchical Design A PLD design ordered in layers or levels. The top level contains components that are themselves complete designs. Lower level components may have even lower level designs embedded within them.
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Default Symbol A graphic symbol used to represent a PLD design as a block. Shows only the design’s inputs and outputs. Used as a component in a hierarchical design.
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Max Plus II
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Enter Symbol
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Graphic Editor (untitled)
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Save File
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Basic System Functions And, or, and not elements can be combined to form various logic functions. A few examples are: The comparison function Basic arithmetic functions
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Basic System Functions The encoding function The decoding function
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Basic System Functions The data selection function
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Basic System Functions The counting function …and other functions such as code conversion and storage. Input pulses 1 CounterParallel output lines Binary code for 1 Binary code for 2 Binary code for 3 Binary code for 4 Binary code for 5 Sequence of binary codes that represent the number of input pulses counted. 2345
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Basic System Functions One type of storage function is the shift register, that moves and stores data each time it is clocked.
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© 2009 Pearson Education, Upper Saddle River, NJ 07458. All Rights ReservedFloyd, Digital Fundamentals, 10 th ed Integrated Circuits Cutaway view of DIP (Dual-In-line Pins) chip: The TTL series, available as DIPs are popular for laboratory experiments with logic.
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