python串口读取数据的实例

import serial
import time
serialport = serial.Serial()
serialport.port = 'COM4'
serialport.baudrate = 115200
serialport.bytesize = 8
serialport.parity = serial.PARITY_NONE
serialport.stopbits = 1
serialport.timeout = 0.001
serialport.close()
if not serialport.is_open:
    serialport.open()
time.sleep(0.05) #时间设置参考串口传输速率
num = serialport.inWaiting()
if num > 0:
    data = serialport.read(num)
    print(data)

import sqlite3
import threading
from datetime import datetime
import serial
import time
def dh():
    t=threading.Timer(1, run)
    t.start()
def run():
    dh()
    serialport = serial.Serial()
    serialport.port = 'COM4'
    serialport.baudrate = 115200
    serialport.bytesize = 8
    serialport.parity = serial.PARITY_NONE
    serialport.stopbits = 1
    serialport.timeout = 20
    serialport.close()
    if not serialport.is_open:
        serialport.open()
    time.sleep(0.5)  # 时间设置参考串口传输速率
    num = serialport.inWaiting()
    if num > 0:
        data = serialport.read(num)# 读取数据解析数据插入sqlite 数据库
        print(  data.decode().strip().split(",")[0])
        sql = "insert into t_table  (code,weight,feedIntake,time)values(?,?,?,?)"
        conn = sqlite3.connect("test.db")
        c = conn.cursor()
        try:
            c.execute(sql, data.decode().strip().split(","))
            conn.commit()
            print("数据插入成功")
        except Exception as e:
            print("数据插入失败", e)
        finally:
            code = data.decode().strip().split(",")[0]
            gg = tuple([code])
            #searchcode(gg)
            conn.close()
        return "数据插入成功"
dh()

# 串口发送数据
def FeedComposia(a,b,c):
    serialport = serial.Serial()
    serialport.port = 'COM3'
    serialport.baudrate = 115200
    serialport.bytesize = 8
    serialport.parity = serial.PARITY_NONE
    serialport.stopbits = 1
    serialport.timeout = 20
    serialport.close()
    if not serialport.is_open:
        serialport.open()
    time.sleep(0.5)  # 时间设置参考串口传输速率
    t=a,b,c #数据要转换一下，才能接受
    v = json.dumps(t, ensure_ascii=False)
    serialport.write(v.encode())
    print("a", a)
    print("b", b)
    return a, b