Linux操作系统下串口的设置
1、查看串口设备
在Linux系统中，串口设备通常位于/dev目录下，可以使用以下命令查看系统中的串口设备：
ls /dev/ttyS* /dev/ttyUSB* /dev/ttyACM*
2、配置串口参数
要使用串口，首先需要配置串口参数，包括波特率、数据位、停止位和校验位等，这些参数可以通过修改/etc/default/grub文件来设置，将波特率设置为9600,数据位设置为8,停止位设置为1,无校验位：
GRUB_CMDLINE_LINUX="console=ttyS0,115200 console=ttyS1,115200"
然后运行sudo update-grub更新grub配置。
3、加载串口驱动
在配置好串口参数后，需要加载相应的串口驱动，不同的Linux发行版可能使用不同的驱动，这里以CentOS为例，使用serial驱动：
sudo yum install -y serial-getty serial-utils
4、启动串口服务
加载驱动后，需要启动串口服务，可以使用以下命令启动串口服务：
sudo systemctl start seriald
5、查看串口状态
要查看串口的状态，可以使用以下命令：
sudo systemctl status seriald
Linux操作系统下串口的编程
1、使用Python操作串口
在Linux系统中，可以使用Python的pyserial库来操作串口，首先需要安装pyserial库：
pip install pyserial
然后可以使用以下代码打开串口并读取数据：
import serial
ser = serial.Serial('/dev/ttyS0', 9600)
print(ser.read(10)) 读取10个字节的数据
ser.close()
2、使用C语言操作串口
在Linux系统中，还可以使用C语言编写程序操作串口，首先需要包含头文件并定义宏：
include <fcntl.h> include <termios.h> include <unistd.h> include <stdio.h> include <string.h> define SERIAL_PORT "/dev/ttyS0" // 串口设备文件名，根据实际情况修改
然后可以编写一个简单的程序来打开串口并读取数据：
int main() { // 主函数入口标志符 and return value and exit status (if applicable) and error code (if applicable) int fileDescriptor; /* Open the serial port */ fileDescriptor = open(SERIAL_PORT, O_RDWR | O_NOCTTY); if (fileDescriptor == -1) { perror("Unable to open serial port"); return 1; } else { printf("Serial port opened successfully
"); } close(fileDescriptor); return 0; } /* Read data from the serial port */ /* This function reads 'numBytes' bytes from the serial port and stores them in 'buffer' *//* The buffer must have at least 'numBytes' bytes of space available *//* Returns the number of bytes read *//* If an error occurs during reading, returns a negative value */ssize_t readSerialPort(char *buffer, size_t numBytes) /* Set serial port options */ /* These options are common for many serial devices */ /* You can modify this table according to your specific device */struct termios options; memset(&options, 0, sizeof(options)); options.c_cflag = B9600 | CS8 | CLOCAL | CREAD; /* Set baud rate to 9600 *//* Set character size to 8 bits *//* Enable canonical mode (no parity check) *//* Enable receiver and set local mode *//* Enable reading from the serial port */options.c_iflag = IGNPAR; /* Clear input flags */options.c_oflag = 0; /* Clear output flags */options.c_lflag = 0; /* Clear local flags */options.c_cc[VMIN] = 0; /* Minimum number of bytes to read at a time */options.c_cc[VTIME] = 5; /* Maximum amount of time between reads (in seconds) */ /* Set the new options for the serial port */ /* Return success or failure */int result = tcsetattr(fileDescriptor, TCSANOW, &options); if (result != 0) { perror("Error setting serial port options"); return result; } else { printf("Serial port options set successfully
"); } return result; } /* Write data to the serial port */ /* This function writes 'numBytes' bytes from 'buffer' to the serial port *//* Returns the number of bytes written *//* If an error occurs during writing, returns a negative value */ssize_t writeSerialPort(char *buffer, size_t numBytes) /* Close the serial port */ /* This is not necessary on most operating systems but it's good practice to close files when you're done with them */ close(fileDescriptor); return result; } /* Example usage */ int main() { int fileDescriptor; char buffer[10]; ssize_t numBytesRead; /* Open the serial port */fileDescriptor = open(SERIAL_PORT, O_RDWR | O_NOCTTY); if (fileDescriptor == -1) { perror("Unable to open serial port"); return 1; } else { printf("Serial port opened successfully
"); } close(fileDescriptor); return 0; } /* Read data from the serial port */ssize_t numBytesRead = readSerialPort(buffer, sizeof(buffer)); if (numBytesRead > 0) { printf("Data received: %s
", buffer); } else { printf("No data received
"); } return 0; } /* Write data to the serial port */ssize_t numBytesWritten = writeSerialPort("Hello, World!", sizeof("Hello, World!")); if (numBytesWritten > 0) { printf("Data sent: Hello, World!
"); } else { printf("No data sent
"); } return 0; } /* Close the serial port */int main() { int fileDescriptor; close(fileDescriptor); return result; } /* Error handling code */int main() { int fileDescriptor; char buffer[10]; ssize_t numBytesRead; /* Open the serial port */fileDescriptor = open(SERIAL_PORT, O_RDWR | O_NOCTTY); if (fileDescriptor == -1) { perror("Unable to open serial port"); return 1; } else { printf("Serial port opened successfully
"); } close(fileDescriptor); return 0; } /* Read data from the serial port */ssize_t numBytesRead = readSerialPort(buffer, sizeof(buffer)); if (numBytesRead > 0) { printf("Data received: %s
", buffer); } else { printf("No data received
"); } return 0; } /* Write data to the serial port */ssize_t numBytesWritten = writeSerialPort("Hello, World!", sizeof("Hello, World!")); if (numBytesWritten > 0) { printf("Data sent: Hello, World!
"); } else { printf("No data sent
"); } return 0; } /* Close the serial port */int main() { int fileDescriptor; close(fileDescriptor); return result; }
原创文章，作者：K-seo，如若转载，请注明出处：https://www.kdun.cn/ask/196053.html
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