Why serial communication is needed in Embedded C

Introduction

Serial communication is needed to send data between devices using fewer wires, making connections simpler and cheaper.

When connecting a microcontroller to a sensor that sends data one bit at a time.

When sending data from a computer to a small device like an Arduino using USB or UART.

When devices are far apart and you want to reduce the number of wires.

When you want to communicate between two devices with limited pins available.

When transferring data slowly but reliably over a single wire or pair of wires.

Syntax

Embedded C

No specific syntax as this is a concept, but serial communication often uses protocols like UART, SPI, or I2C.

Serial communication sends data one bit after another, unlike parallel communication which sends many bits at once.

It is common in embedded systems because it uses fewer wires and is easier to manage.

Examples

This shows a typical setup function for serial communication using UART in embedded C.

Embedded C

// Example: UART initialization in embedded C
void UART_Init() {
    // Set baud rate, frame format, enable transmitter and receiver
}

This function waits until the transmitter is ready and then sends one byte.

Embedded C

// Example: Sending a byte over UART
void UART_SendByte(unsigned char data) {
    while (!(UART_STATUS & TX_READY));
    UART_DATA = data;
}

Sample Program

This simple program simulates sending data one character at a time, like serial communication does.

Embedded C

#include <stdio.h>

// Simulated function to show why serial communication is useful
void sendDataSerially(char *data) {
    // Imagine sending one character at a time
    while (*data) {
        printf("Sending: %c\n", *data);
        data++;
    }
}

int main() {
    char message[] = "HELLO";
    sendDataSerially(message);
    return 0;
}

Important Notes

Serial communication reduces the number of wires needed, which saves space and cost.

It is slower than parallel communication but simpler and more reliable over long distances.

Common serial protocols include UART, SPI, and I2C, each with different uses.

Summary

Serial communication sends data bit by bit using fewer wires.

It is useful for connecting devices with limited pins or over long distances.

Embedded systems often use serial communication to talk to sensors and other devices.