CSF117 Module 5 Wired Communication

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Welcome to the Wired Communication module. This module aims to facilitate learning of the various ways you can interconnect components together to a microcontroller such as Arduino for purposes of sending and receiving data.
Hello and welcome to communication in IoT. In the previous modules, we focused on the sensory or perception layer in the IoT architecture where we learned about sensors and actuators. We learned how to obtain sensory information from the environment. Afterwhich, you may wish to send that sensory data to another device or even to the cloud for further processing or even monitoring by you or other users. The sending and receiving or data happens in the network or data transport layer. For data transmission to happen among a web-of-devices or from a device to the cloud, several communication devices and protocols may be used. Either wired or wireless. Example protocols for wired communication include; Serial Peripheral Interface Bus (SPI), Inter-integrated circuit (I2C), Recommended Standard 232 (RS 232), UART/USART Protocols and USB. For internal communication where a microcontroller communicates with a component, we have i2C and SPI. i2C uses two wires and can connect more than one component (called a slave) to a microcontroller (called a master) such as an Arduino. The two wires are for data and clock signaling. SPI uses four wires per slave. It supports addressing such that the master can pick which slave to communicate with. It works for short distances. For external communication where a microcontroller device communicates with another microcontroller, we have Ethernet, RS232, UART and USB. RS232 is mostly used in computer serial ports. It uses several wires and works mostly by specifying timing requirements at different data rates/speeds. The UART protocol uses only one wire and depends on clock accuracy for both the sending and receiving component. UART is a very low cost wired communication system.