python-serial port

website

conda install pyserial
or 
pip3 install pyserial

readline

readline 需要 \n 结尾

import serial

def simulate_DL_RS1A():
    try:
        # 端口，GNU / Linux上的/ dev / ttyUSB0 等 或 Windows上的 COM3 等
        port = "COM2"
        # 波特率，标准值之一：50,75,110,134,150,200,300,600,1200,1800,2400,4800,9600,19200,38400,57600,115200
        baudrate = 19200
        # 超时设置,None：永远等待操作，0为立即返回请求结果，其他值为等待超时时间(单位为秒）
        timeout = 5
        ser = serial.Serial(port, baudrate, timeout=timeout)
        # 循环读取数据
        while True:
            line = ser.readline().decode("gbk")
            if line.startswith('M0\r\n'):
                result = ser.write("M0,-00.029,+00.043,+00.056,-00.038,+00.037,+00.018,-00.229,+00.030\r\n".encode("gbk"))
                pass

        # 写数据
        result = ser.write("123456".encode("gbk"))
        print("字节数:", result)
        ser.close()  # 关闭串口
    except Exception as e:
        import traceback
        traceback.print_exc()
        errMsg = traceback.format_exc()
        print("Error: 异常，无法发送邮件: " + errMsg)
    except:
        import traceback
        traceback.print_exc()
        errMsg = traceback.format_exc()
        print("Error: 未知异常，无法发送邮件: " + errMsg)
    pass

read

read(size=1)
Parameters: size – Number of bytes to read.
Returns: Bytes read from the port.
Return type: bytes
Read size bytes from the serial port. If a timeout is set it may return less characters as requested. With no timeout it will block until the requested number of bytes is read.

Changed in version 2.5: Returns an instance of bytes when available (Python 2.6 and newer) and str otherwise.