Communication between MCU and PC

Communication between microcontrollers and personal computers (PCs) is a crucial part of embedded system development. Serial communication is one of the most commonly used methods for communication between microcontrollers and PCs. This article will introduce the basic principles and methods of serial communication to help readers understand how to achieve reliable data transfer between microcontrollers and PCs.

Serial communication is a method of transmitting data from one device to another through a serial communication interface. In serial communication between a microcontroller and a PC, the microcontroller acts as the sender or receiver, while the PC acts as the receiver or sender.

The basic principle of serial communication involves dividing data into bytes and transmitting them according to certain rules from the sender to the receiver, who then reassembles the received bytes into complete data.

 

The core of serial communication is the use of serial port protocols for data transmission. Common serial port protocols include RS-232, RS-485, etc. In serial communication between microcontrollers and PCs, the most commonly used protocol is RS-232.

 

To communicate between a microcontroller and a PC via serial port, appropriate communication interfaces and protocols are required. Below is a commonly used method for serial communication:

First, connect the microcontroller's serial port pins to the PC's serial port interface. Typically, the microcontroller's serial port pins include a transmit pin (TX) and a receive pin (RX), while the PC's serial port interface also has corresponding transmit and receive pins.

 

By connecting the serial port pins, the microcontroller and PC can communicate through physical wiring.

Before serial communication can occur, the serial ports on both the microcontroller and PC need to be set up appropriately. Communication settings include parameters such as baud rate, data bits, stop bits, and parity.

 

Baud rate refers to the number of bits transmitted per unit of time and common rates include 9600, 115200, etc. Data bits refer to the number of bits in each byte, with common options being 8 bits, 9 bits, etc. Stop bits are the number of bits used to mark the end of each byte and common stop bit options are 1 bit, 2 bits, etc. Parity is a method for checking the integrity of data transmission.

After communication settings are completed, data transmission can begin. In the microcontroller, the data to be sent is written into the transmit buffer through appropriate programming, and then sent out through the serial port. On the PC, the receive buffer is accessed through corresponding programming to read the received data.

 

During data transmission, attention must be paid to data format and the order of transmission to ensure accuracy and integrity of the data.

Serial communication has a wide range of applications in embedded system development. Through serial communication, a microcontroller can interact with a PC, enabling various functions.

Common applications of serial communication include sensor data collection and transmission, remote control and monitoring, data storage, and processing, among others.

This article introduced the basic principles and methods of serial communication between microcontrollers and PCs. By following steps such as hardware connection, communication settings, and data transmission, reliable data transfer can be achieved between microcontrollers and PCs. Serial communication is an important application in embedded system development, and readers can apply the methods described in this article to practical scenarios.