**Table 8.**

*Truth Table – Gray to Binary Code Converter.*

such that each incremental value can only differ by one bit. The main objective in this code converter is that while traversing from one step to another step, one bit in the code group changes as in **Figure 9**. This gray code is not applicable for arithmetic operations, but it is applicable in analog to digital converters, as well as error

**G3 G2 G1 G0 B3 B2 B1 B0** 0 00 00000 0 00 1 0001 0 0 1 1 0010 0 0 1 0001 1 0 1 1 00100 0 1 1 10101 0 10 10110 0 1000111 1 1 0 0 1000 1 1 0 1 1001 1 1 1 1 1010 1 1 1 01011 1 0 1 0 1 100 1 01 1 1101 1 00 1 1110 1 0001111

*B*<sup>3</sup> ¼ *G*<sup>3</sup> (22) *B*<sup>2</sup> ¼ *G*<sup>2</sup> ⨁*G*<sup>3</sup> (23) *B*<sup>1</sup> ¼ *G*<sup>1</sup> ⨁*G*<sup>2</sup> ⨁*G*<sup>3</sup> (24) *B*<sup>0</sup> ¼ *G*<sup>1</sup> ⨁*G*<sup>2</sup> ⨁*G*<sup>3</sup> ⨁*G*<sup>0</sup> (25)

correction techniques in digital communications (**Table 8**).

*LabVIEW - A Flexible Environment for Modeling and Daily Laboratory Use*

**Figure 9.**

**Table 8.**

**166**

*Logic Diagram – Gray to Binary Code Converter.*

*Truth Table – Gray to Binary Code Converter.*

**Figure 10.** *Logic Diagram – Seven Segment Decoder.*

#### *3.4.3 Seven segment decoder*

A digital decoder IC is a device that converts one digital format into another, and one of the most commonly-used device for doing this is the binary-coded decimal (BCD) to 7-segment display decoder. The 7-segment light emitting diode (LED) provides a convenient way of displaying information or digital data in the form of numbers, letters and alphanumeric characters. Typically, 7-segment displays consist of seven same coloured LEDs (called segments) within a single display package. In order to display the correct character or number, the correct combination of LED segments has to be illuminated. This LabVIEW program demonstrates the illumination of each segment by displaying hex values (0000 through FFFF) in decimal form from 0 through 9 and A through F. The standard 7-segment LED display has eight input connections, one for each LED segment and one that acts as a common terminal or connection for all internal display segments. Some displays also have an additional input pin for displaying a decimal point.

#### *3.4.4 Types of digital display*

There are two important types of 7-segment LED displays, namely, common cathode and common anode. In Common cathode display (CCD) display, all cathode connections of the LEDs are joined together to a low logic or ground or 0 [5]. The individual segment is illuminated by the application of high logic or + Vcc or 1 to the individual anode terminal. In Common anode display (CAD) In a CAD, all anode connections of the LEDs are joined together to a high logic or + Vcc and individual segments are illuminated by connecting individual cathode terminals to low logic or ground as shown in **Figure 10**. The boolean expressions of the outputs.

$$a = \overline{A}BD + A\overline{B}\overline{C} + \overline{B}\overline{D} + AC + A\overline{D} + BC \tag{26}$$

$$b = \overline{A}C \oplus D + A(C \oplus D) + \overline{BC} + \overline{BD} \tag{27}$$

$$\mathcal{L} = \overline{B}\overline{C} + \overline{B}D + \overline{C}D + \overline{A}B + A\overline{B} \tag{28}$$

$$\mathbf{d} = \overline{B\overline{C}D} + \overline{B}DC + \overline{A}C\overline{D} + B\overline{C}D + A\overline{C} + AB\overline{D} \tag{29}$$

$$e = \overline{BD} + C\overline{D} + AB + AC \tag{30}$$

**Author details**

*Digital System Design*

*DOI: http://dx.doi.org/10.5772/intechopen.97611*

Janani Rajaraman

**169**

Kanchipuram, Tamilnadu, India

provided the original work is properly cited.

Department of Electronics and Instrumentation Engineering, Sri Chandrasekharendra Saraswathi Viswa Mahavidyalaya, Enathur,

\*Address all correspondence to: janani.rajaraman@kanchiuniv.ac.in

© 2021 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

$$f = \overline{A}B\overline{C} + \overline{C}\overline{D} + B\overline{D} + A\overline{B} + AC \tag{31}$$

$$\mathbf{g} = \overline{A}B\overline{D} + B\overline{C}D + A\overline{B} + AC + C\overline{B} \tag{32}$$

### **4. Conclusion**

This chapter brings an overview of design of combinational logic circuits in LabVIEW. This LabVIEW programming tool is a graphical representation tool which helps the designer to simplify the design work. This tool can be further extended for designing sequential circuits as well as PLA and PAL logic design.

### **Acknowledgements**

The author would like to thank the Department of Electronics and Instrumentation Engineering of Sri Chandrasekharendra Saraswathi Viswa Mahavidyalaya, Enathur, Kanchipuram, India, for providing online library facility as well as for permitting to use the lab environment.

*Digital System Design DOI: http://dx.doi.org/10.5772/intechopen.97611*

*3.4.3 Seven segment decoder*

*3.4.4 Types of digital display*

**4. Conclusion**

**Acknowledgements**

**168**

permitting to use the lab environment.

additional input pin for displaying a decimal point.

A digital decoder IC is a device that converts one digital format into another, and one of the most commonly-used device for doing this is the binary-coded decimal (BCD) to 7-segment display decoder. The 7-segment light emitting diode (LED) provides a convenient way of displaying information or digital data in the form of numbers, letters and alphanumeric characters. Typically, 7-segment displays consist of seven same coloured LEDs (called segments) within a single display package. In order to display the correct character or number, the correct combination of LED segments has to be illuminated. This LabVIEW program demonstrates the illumination of each segment by displaying hex values (0000 through FFFF) in decimal form from 0 through 9 and A through F. The standard 7-segment LED display has eight input connections, one for each LED segment and one that acts as a common terminal or connection for all internal display segments. Some displays also have an

*LabVIEW - A Flexible Environment for Modeling and Daily Laboratory Use*

There are two important types of 7-segment LED displays, namely, common cathode and common anode. In Common cathode display (CCD) display, all cathode connections of the LEDs are joined together to a low logic or ground or 0 [5]. The individual segment is illuminated by the application of high logic or + Vcc or 1 to the individual anode terminal. In Common anode display (CAD) In a CAD, all anode connections of the LEDs are joined together to a high logic or + Vcc and individual segments are illuminated by connecting individual cathode terminals to low logic or

This chapter brings an overview of design of combinational logic circuits in LabVIEW. This LabVIEW programming tool is a graphical representation tool which helps the designer to simplify the design work. This tool can be further extended for designing sequential circuits as well as PLA and PAL logic design.

The author would like to thank the Department of Electronics and Instrumenta-

tion Engineering of Sri Chandrasekharendra Saraswathi Viswa Mahavidyalaya, Enathur, Kanchipuram, India, for providing online library facility as well as for

*a* ¼ *ABD* þ *ABC* þ *BD* þ *AC* þ *AD* þ *BC* (26) *b* ¼ *AC*⨁*D* þ *A C*ð Þþ ⨁*D BC* þ *BD* (27) *c* ¼ *BC* þ *BD* þ *CD* þ *AB* þ *AB* (28)

d ¼ *BCD* þ *BDC* þ *ACD* þ *BCD* þ *AC* þ *ABD* (29)

*e* ¼ *BD* þ *CD* þ *AB* þ *AC* (30)

*f* ¼ *ABC* þ *CD* þ *BD* þ *AB* þ *AC* (31) *g* ¼ *ABD* þ *BCD* þ *AB* þ *AC* þ *CB* (32)

ground as shown in **Figure 10**. The boolean expressions of the outputs.
