串口操作

1. 基本操作

import serial	# 引入 serial 库
import serial.tools.list_ports

port_list = list(serial.tools.list_ports.comports())	# 搜索串口列表

ser = serial.Serial(com, int(bps), timeout=int(timex))

ser.flushInput()	# 清空缓冲区

count = ser.inWaiting() # 获取缓冲区字符数量

str = ser.readline(ser.in_waiting) # 读取内容并回显

str = glo.ser.read(ser.in_waiting)

2. 搜索串口

class getCom(QThread):
    comUpdate = pyqtSignal(list)
    port_list_orignal = []

    def run(self):
        """得到所有的串口号
        args: NONE
        return: (串口号列表: ['COM1', ...], 串口名列表: ['通信端口 (COM1)'], 串口列表: ['COM1 - 通信端口 (COM1)', ...])
        """
        while(True):
            port_list = list(serial.tools.list_ports.comports())
            if set(port_list) != set(self.port_list_orignal):
                self.port_listUpdate(port_list)
                if len(port_list) == 0:
                    print('No serial port found!')
                    exit()
                else:
                    self.comUpdate.emit(port_list)

    def port_listUpdate(self, port_list):
        self.port_list_orignal = port_list

• 串口的相关信息

  • | 描述 | 函数 | 示例输出 |
    | ————- | ———————— | —————————————————————————— |
    | 串口信息 | port | COM7 - Silicon Labs CP210x USB to UART Bridge (COM7) |
    | 设备名 | name | COM7 |
    | 设备号 | device | COM7 |
    | 设备描述 | description | Silicon Labs CP210x USB to UART Bridge (COM7) |
    | 硬件 ID | hwid | USB VID:PID=10C4:EA60 SER=0001 LOCATION=1-5 |
    | 供应商 ID | vid | 4292 |
    | 产品 ID | pid | 60000 |
    | 序列号 | serial_number | 0001 |
    | 位置 | location | 1-5 |
    | 制造商 | manufacturer | Silicon Labs |
    | 产品 | product | None |
    | 接口 | interface | None |
    | USB 信息 | usb_info() | USB VID:PID=10C4:EA60 SER=0001 LOCATION=1-5 |
    | USB 描述 | usb_decription() | COM7 |

3. 打开串口

def serialOpen(com, bps, timex):
    """打开串口
    args: com: 串口号; bps: 波特率; timex: 超时时间
    return: ser: 串口对象
    """
    try:
        ser = serial.Serial(com, int(bps), timeout=int(timex))
        if ser.isOpen():
            print('open success')
            return ser
        else:
            print('open failed')
            return None
    except:
        print("serialOpen: 串口不存在")
        return
    finally:
        ...

• 打开串口参数

  • ```python
    port = None, # 设备名
    baudrate = 9600, # 波特率
    bytesize = EIGHTBITS, # 数据位
    parity = PARITY_NONE, # 奇偶校验
    stopbits = STOPBITS_ONE, # 停止位
    timeout = None, # 读超时
    xonxoff = False, # 软件流控
    rtscts = False, # 硬件流控
    write_timeout = None, # 写超时
    dsrdtr = False, # DSR/DTR
    inter_byte_timeout = None, # 字节间隔超时
    exclusive = None, # 独占端口

    # 4. 串口数据读取
    
    ```python
    class serialRead_original(QThread):
        dateReadUpdate = pyqtSignal(str)	# 数据更新信号
        serDisconnect = pyqtSignal()	# 串口断开信号
    
        def run(self):
            """读取串口数据
            args: NONE
            return: NONE
            """
            print("serialRead start")
            ser.flushInput()	# 清空缓冲区
            while(isConnected):
                if serialIsOpen(ser) == False:	# 串口断开 或 不存在
                    print("serialRead stop")
                    self.serDisconnect.emit()
                    serialClose(ser)
                    break
                count = ser.inWaiting() # 获取缓冲区字符数量
                # print("count: ", count)
                if count != 0:
                    str = ser.readline(ser.in_waiting) # 读取内容并回显
                    # str = glo.ser.read(ser.in_waiting)
                    # str -> b'' => 二进制数据
                    # str = str.decode(encoding='utf-8', errors='ignore')
                    self.dateReadUpdate.emit(str)
                    # print('data:', data)
                sleep(1)