This document discusses serial communication and data transmission. It explains that for successful communication, the receiver and transmitter must agree on communication protocols. It then describes the transmission mode and how data is formatted with start bits, data bits, parity bits, and stop bits. The document also briefly mentions the RS-232C and RS-485 interfaces and provides a comparison of serial communication methods.

1. Serial
Communication
Yong Heui Cho @ Mokwon University
Some of slides are referred to:
[1] Sabatiana, Maulina, Nugraha, Serial Data Communication, slideshare.

2. Basic Computer Design
10. Role of CPU
11. CPU and Software
12. Analog and Digital I/O
13. Serial Communication

3. 3
Communication
• Both the receiver and the transmitter must
agree on a number of different factors to
allow successful communications between
them, the most important being: protocols
3□ Courtesy to Serial Data Communication, slideshare.
SOURCE RECEIVER
COMMUNICATION
LINK

4. 4
Transmission Mode
4□ Courtesy to Serial Data Communication, slideshare.

5. 5
Data Format
• Data is usually arranged in a particular format, with additional
information added so that the message can be effectively
transmitted and understood at the receiving end. In summary, the
optional settings for asynchronous transmission of characters are:
– Start bit: 1
– Data bits: 5, 6, 7, 8
– Parity bits: even, odd, mark, space or none
– Stop bits: 1, l½ or 2
• As there cannot be half a bit, 1½-stop bits means that the mark
length is 50% longer than for one stop bit.
5□ Courtesy to Serial Data Communication, slideshare.

6. 6
RS-232C Interface
6□ Courtesy to Serial Data Communication, slideshare.

7. 7
RS-485 Interface
7□ Courtesy to Serial Data Communication, slideshare.

8. 8
Comparison
8□ Courtesy to Serial Data Communication, slideshare.