python控制TLP2041高压电源源码（modbus rtu，try捕获异常使用）

gui：

# -*- coding: utf-8 -*-

# Form implementation generated from reading ui file 'PGUI.ui'
#
# Created by: PyQt5 UI code generator 5.15.1
#
# WARNING: Any manual changes made to this file will be lost when pyuic5 is
# run again.  Do not edit this file unless you know what you are doing.


from PyQt5 import QtCore, QtGui, QtWidgets


class Ui_MainWindow(object):
    def setupUi(self, MainWindow):
        MainWindow.setObjectName("MainWindow")
        MainWindow.resize(800, 600)
        self.centralwidget = QtWidgets.QWidget(MainWindow)
        self.centralwidget.setObjectName("centralwidget")
        self.verticalLayout_2 = QtWidgets.QVBoxLayout(self.centralwidget)
        self.verticalLayout_2.setObjectName("verticalLayout_2")
        self.verticalLayout = QtWidgets.QVBoxLayout()
        self.verticalLayout.setObjectName("verticalLayout")
        self.horizontalLayout = QtWidgets.QHBoxLayout()
        self.horizontalLayout.setObjectName("horizontalLayout")
        self.comboBox = QtWidgets.QComboBox(self.centralwidget)
        font = QtGui.QFont()
        font.setFamily("Times New Roman")
        font.setPointSize(20)
        self.comboBox.setFont(font)
        self.comboBox.setObjectName("comboBox")
        self.horizontalLayout.addWidget(self.comboBox)
        self.pushButton = QtWidgets.QPushButton(self.centralwidget)
        font = QtGui.QFont()
        font.setFamily("Times New Roman")
        font.setPointSize(20)
        self.pushButton.setFont(font)
        self.pushButton.setObjectName("pushButton")
        self.horizontalLayout.addWidget(self.pushButton)
        self.verticalLayout.addLayout(self.horizontalLayout)
        self.horizontalLayout_2 = QtWidgets.QHBoxLayout()
        self.horizontalLayout_2.setObjectName("horizontalLayout_2")
        self.verticalLayout_3 = QtWidgets.QVBoxLayout()
        self.verticalLayout_3.setObjectName("verticalLayout_3")
        self.label_2 = QtWidgets.QLabel(self.centralwidget)
        sizePolicy = QtWidgets.QSizePolicy(QtWidgets.QSizePolicy.Preferred, QtWidgets.QSizePolicy.Fixed)
        sizePolicy.setHorizontalStretch(0)
        sizePolicy.setVerticalStretch(0)
        sizePolicy.setHeightForWidth(self.label_2.sizePolicy().hasHeightForWidth())
        self.label_2.setSizePolicy(sizePolicy)
        font = QtGui.QFont()
        font.setFamily("Times New Roman")
        font.setPointSize(24)
        self.label_2.setFont(font)
        self.label_2.setAlignment(QtCore.Qt.AlignCenter)
        self.label_2.setObjectName("label_2")
        self.verticalLayout_3.addWidget(self.label_2)
        self.lineEdit = QtWidgets.QLineEdit(self.centralwidget)
        font = QtGui.QFont()
        font.setFamily("Times New Roman")
        font.setPointSize(20)
        self.lineEdit.setFont(font)
        self.lineEdit.setObjectName("lineEdit")
        self.verticalLayout_3.addWidget(self.lineEdit)
        self.horizontalLayout_2.addLayout(self.verticalLayout_3)
        self.verticalLayout_4 = QtWidgets.QVBoxLayout()
        self.verticalLayout_4.setObjectName("verticalLayout_4")
        self.label_3 = QtWidgets.QLabel(self.centralwidget)
        sizePolicy = QtWidgets.QSizePolicy(QtWidgets.QSizePolicy.Preferred, QtWidgets.QSizePolicy.Fixed)
        sizePolicy.setHorizontalStretch(0)
        sizePolicy.setVerticalStretch(0)
        sizePolicy.setHeightForWidth(self.label_3.sizePolicy().hasHeightForWidth())
        self.label_3.setSizePolicy(sizePolicy)
        font = QtGui.QFont()
        font.setFamily("Times New Roman")
        font.setPointSize(24)
        self.label_3.setFont(font)
        self.label_3.setAlignment(QtCore.Qt.AlignCenter)
        self.label_3.setObjectName("label_3")
        self.verticalLayout_4.addWidget(self.label_3)
        self.lineEdit_2 = QtWidgets.QLineEdit(self.centralwidget)
        font = QtGui.QFont()
        font.setFamily("Times New Roman")
        font.setPointSize(20)
        self.lineEdit_2.setFont(font)
        self.lineEdit_2.setObjectName("lineEdit_2")
        self.verticalLayout_4.addWidget(self.lineEdit_2)
        self.horizontalLayout_2.addLayout(self.verticalLayout_4)
        self.verticalLayout.addLayout(self.horizontalLayout_2)
        self.horizontalLayout_3 = QtWidgets.QHBoxLayout()
        self.horizontalLayout_3.setObjectName("horizontalLayout_3")
        self.pushButton_3 = QtWidgets.QPushButton(self.centralwidget)
        sizePolicy = QtWidgets.QSizePolicy(QtWidgets.QSizePolicy.Preferred, QtWidgets.QSizePolicy.Fixed)
        sizePolicy.setHorizontalStretch(0)
        sizePolicy.setVerticalStretch(0)
        sizePolicy.setHeightForWidth(self.pushButton_3.sizePolicy().hasHeightForWidth())
        self.pushButton_3.setSizePolicy(sizePolicy)
        font = QtGui.QFont()
        font.setFamily("Times New Roman")
        font.setPointSize(20)
        self.pushButton_3.setFont(font)
        self.pushButton_3.setObjectName("pushButton_3")
        self.horizontalLayout_3.addWidget(self.pushButton_3)
        self.pushButton_2 = QtWidgets.QPushButton(self.centralwidget)
        font = QtGui.QFont()
        font.setFamily("Times New Roman")
        font.setPointSize(20)
        self.pushButton_2.setFont(font)
        self.pushButton_2.setObjectName("pushButton_2")
        self.horizontalLayout_3.addWidget(self.pushButton_2)
        self.verticalLayout.addLayout(self.horizontalLayout_3)
        self.textBrowser = QtWidgets.QTextBrowser(self.centralwidget)
        sizePolicy = QtWidgets.QSizePolicy(QtWidgets.QSizePolicy.Expanding, QtWidgets.QSizePolicy.Expanding)
        sizePolicy.setHorizontalStretch(0)
        sizePolicy.setVerticalStretch(0)
        sizePolicy.setHeightForWidth(self.textBrowser.sizePolicy().hasHeightForWidth())
        self.textBrowser.setSizePolicy(sizePolicy)
        font = QtGui.QFont()
        font.setFamily("Times New Roman")
        font.setPointSize(16)
        self.textBrowser.setFont(font)
        self.textBrowser.setObjectName("textBrowser")
        self.verticalLayout.addWidget(self.textBrowser)
        self.verticalLayout_2.addLayout(self.verticalLayout)
        MainWindow.setCentralWidget(self.centralwidget)

        self.retranslateUi(MainWindow)
        QtCore.QMetaObject.connectSlotsByName(MainWindow)

    def retranslateUi(self, MainWindow):
        _translate = QtCore.QCoreApplication.translate
        MainWindow.setWindowTitle(_translate("MainWindow", "菜芽"))
        self.pushButton.setText(_translate("MainWindow", "开启串口"))
        self.label_2.setText(_translate("MainWindow", "电压设定值/kV"))
        self.label_3.setText(_translate("MainWindow", "电流设定值/mA"))
        self.pushButton_3.setText(_translate("MainWindow", "高压开关"))
        self.pushButton_2.setText(_translate("MainWindow", "读取电压电流"))

主代码：

from sys import argv,exit
import serial
from PyQt5.QtCore import QTimer
from PyQt5.QtWidgets import QApplication, QMainWindow
from modbus_tk import modbus_rtu
import PGUI


class my_mainwindow():
    def __init__(self):
        # PyQt5中，每个应用程序都必须实例化一个QApplication()：
        app = QApplication(argv)
        self.my_MainWindow = QMainWindow()
        self.my_ui = PGUI.Ui_MainWindow()
        self.my_ui.setupUi(self.my_MainWindow)
        ####################################################################
        self.mycom = ['com1', 'com2', 'com3', 'com4', 'com5', 'com6']
        self.my_ui.comboBox.addItems(self.mycom)
        self.my_ui.pushButton.setStyleSheet("background-color: green")
        self.my_ui.pushButton_3.setStyleSheet("background-color: green")
        self.serialcolor=1
        self.hand=1
        self.open=0
        self.my_ui.lineEdit.setText('0.5')
        self.my_ui.lineEdit_2.setText('30')
        ####################################################################
        self.timer = QTimer()
        self.timer.timeout.connect(self.showTime)
        self.timer.start(1000)
        self.click_pushbutton()
        #####################################################################
        self.my_MainWindow.show()
        exit(app.exec_())

    def click_pushbutton(self):
        self.my_ui.pushButton.clicked.connect(self.pccontrol)
        self.my_ui.pushButton_2.clicked.connect(self.read)
        self.my_ui.pushButton_3.clicked.connect(self.set)

    def pccontrol(self):
        if self.serialcolor==0:
            if self.open==1:
                self.my_ui.textBrowser.setText('通讯还没有结束')
            else:
                self.my_ui.pushButton.setStyleSheet("background-color: green")
                self.serialcolor = 1
                self.ser.close()
                self.my_ui.textBrowser.setText('串口关闭')
        else :
            try:  # 捕获异常
                self.ser = serial.Serial(port=self.my_ui.comboBox.currentText(), baudrate=9600, bytesize=8, parity='N', stopbits=1)
                self.master = modbus_rtu.RtuMaster(self.ser)
            except:
                self.my_ui.textBrowser.append('串口打开失败')
            else:
                self.master.set_timeout(10)
                self.master.set_verbose(True)
                self.my_ui.textBrowser.setText('打开串口成功')
                self.my_ui.pushButton.setStyleSheet("background-color: red")
                self.serialcolor = 0

    def read(self):
        if self.serialcolor==1:
            self.my_ui.textBrowser.setText('打开串口')
        else:
            try:  # 捕获异常
                read = self.master.execute(1, 4, 0, 2)#读取电压电流实际输出值
            except:
                self.my_ui.textBrowser.setText('通讯失败')
            else:
                self.my_ui.textBrowser.setText('输出电压=%f'%(read[0]*50*1.2/65535))
                self.my_ui.textBrowser.append('输出电流=%f'%(read[1] * 120 * 1.2 / 65535))

    def set(self):
        if self.serialcolor==1:
            self.my_ui.textBrowser.setText('打开串口')
        else:
            if self.hand == 0:
                self.my_ui.pushButton_3.setStyleSheet("background-color: green")
                self.hand = 1
                self.my_ui.textBrowser.setText('高压开关--关')
                self.open=0
            else:
                try:  # 捕获异常
                    read=self.master.execute(1,2,0x0a,1)#读取高压开关状态
                except:
                    self.my_ui.textBrowser.setText('通讯失败')
                else:
                    read = self.master.execute(1, 5, 0x0a, output_value=1)  # 读取高压开关状态
                    self.my_ui.textBrowser.setText('控制打开')
                    read = self.master.execute(1, 5, 0, output_value=1)  # 读取高压开关状态
                    self.my_ui.textBrowser.append('输出打开')
                    setvstr=self.my_ui.lineEdit.text()
                    setvfloat=float(setvstr)
                    setv=int(setvfloat*65535/(50*1.2))
                    setistr = self.my_ui.lineEdit_2.text()
                    setifloat = float(setistr)
                    seti = int(setifloat * 65535 / (120*1.2))
                    read = self.master.execute(1, 6, 0, output_value=setv)
                    read = self.master.execute(1, 6, 1, output_value=seti)
                    self.my_ui.pushButton_3.setStyleSheet("background-color: red")
                    self.hand = 0
                    self.open=1

    def showTime(self):
        if self.open==1:
            read = self.master.execute(1, 2, 0x0a, 1)  # 读取高压开关状态





if __name__=="__main__":
    my_mainwindow()

 try 捕获异常，并将报错信息print出来

        try:
            send_datas = senddata
            ser.write(str(send_datas).encode("gbk"))
        except Exception as exc:
            returnlist=str(exc)
            print(returnlist)
        else:
            print("没问题")