这篇文章主要介绍了python之pyqt多线程串口代码分析,小编觉得挺不错的，现在分享给大家，也给大家做个参考。一起跟随小编过来看看吧
这篇博客主要记录一下pyqt多线程串口的主要代码分析，文末会有工程的源代码文件
首先，从pycharm启动qtdesigner
之前给客户做的上位机，保密起见，删减了大部分的框图构件，但不影响本篇串口教程
qtdesigner界面如下：
忽略 添加数据以及表格数据显示，这里用不到
着重讲一下类的构成
新建一个串口类serialthread，继承自qtcore.qthread，实现全部的串口收发功能
class serialthread(qtcore.qthread): datareadoutsignal = pyqtsignal(str) def __init__(self, parent = none, portname = 'com3', baudrate = 9600, parity = 'n', bytesize = 8, stopbits = 1, timeout = none): super(serialthread, self).__init__(parent) self.m_serialport = serial.serial() self.m_serialport.port = portname self.m_serialport.baudrate = baudrate self.m_serialport.parity = parity self.m_serialport.bytesize = bytesize self.m_serialport.stopbits = stopbits self.m_serialport.timeout = timeout self.openscom() def openscom(self): try: self.m_serialport.open() self.m_serialport.setrts(true) self.m_serialport.setdtr(true) except exception as ex: print(ex) return ex def scomsendonedata(self,datain): if isinstance(datain,int): listtemp = [] listtemp.append(datain) d = bytes(listtemp) self.m_serialport.write(d) else: if isinstance(datain,str): d = datain.encode('utf-8') self.m_serialport.write(d) def scomgetintdata(self): n = self.m_serialport.inwaiting() if n: data = self.m_serialport.read(n).hex() #writefile print(data) def scomgetstrdata(self): if self.m_serialport.is_open: n = self.m_serialport.inwaiting() if n > 0: data = self.m_serialport.read(n).decode('gb2312',errors='ignore') return data def run(self): cnt = 50 while cnt <= 3000: sendstr = str(cnt) if len(sendstr) == 2: sendstr = '00' + sendstr else: if len(sendstr) == 3: sendstr = '0' + sendstr self.scomsendonedata('set' + sendstr + 'v') cnt = cnt + 5 print('此时设置电压为：' + sendstr + 'v') time.sleep(2)
函数功能见名知意，此处不表。这里主要讲一下run函数，run函数实现了一次循环，50到3000步进取5，发送内容是set0050v到set3000v，当然，我这样做是业务需求，如果并不需要这个功能，run函数可以写成
def run(self): while true: time.sleep(2)
界面我们用qtdesigner制作的ui文件通过pyuic生成py文件
生成的代码如下（太长，只留前几行）
# -*- coding: utf-8 -*-# form implementation generated from reading ui file 'cashupdateui11v.ui'## created by: pyqt5 ui code generator 5.6## warning! all changes made in this file will be lost!from pyqt5 import qtcore, qtgui, qtwidgetsclass ui_cash(object): def setupui(self, cash): ** ** **
此时，新建一个类mywindow，继承qmainwindow和ui_cash，并在类内部，创建serialthread成员
总体代码如下：
class mywindow(qmainwindow,ui_cash): def __init__(self): super(mywindow,self).__init__() self.scomlist = [] self.threadlist = [] self.setupui(self) self.actionopen.triggered.connect(self.openmsg) self.actionsave.triggered.connect(self.savemsg) self.pushbutton.clicked.connect(self.scomautofind) self.adddatabutton.clicked.connect(self.getrhandt) self.tablewidget.setcolumncount(5) self.tablewidget.setrowcount(1) self.tablewidget.sethorizontalheaderlabels(['11', '22', '33', '44', '55']) self.tablerowcnt = 0 self.tablecolumncnt = 0 self.threadcomid = 0 self.adddatasignal = pyqtsignal(str) self.datadict = {'rhldy':0,'tldy':0,'meart':0,'voltport':0} def getmcudata(self): if self.threadcomid == 0: self.showmsgbox('请先连接串口') else: self.threadcomid.scomsendonedata(' 5501aa') time.sleep(0.1) strt = self.threadcomid.scomgetstrdata() if strt is none: self.showmsgbox('请将串口线连接到电路板') return none print(strt) self.datadict['voltport'] = strt[4:-3] + '.' + strt[-3:-2] self.threadcomid.scomsendonedata(' 5502aa') time.sleep(0.1) strt = self.threadcomid.scomgetstrdata() if strt is none: self.showmsgbox('请将串口线连接到电路板') return none print(strt) self.datadict['meart'] = strt[4:-4] + '.' + strt[-4:-2] return 1 def inserttablenewline(self): self.tablewidget.setitem(self.tablerowcnt, 0, qtablewidgetitem(self.datadict['rhldy'])) self.tablewidget.setitem(self.tablerowcnt, 1, qtablewidgetitem(self.datadict['tldy'])) self.tablewidget.setitem(self.tablerowcnt, 2, qtablewidgetitem(self.datadict['meart'])) self.tablewidget.setitem(self.tablerowcnt, 3, qtablewidgetitem(self.datadict['voltport'])) self.tablewidget.setitem(self.tablerowcnt, 4, qtablewidgetitem(str(datetime.date.today())+' '+str(datetime.datetime.today().hour)+':'+str(datetime.datetime.today().minute))) self.tablerowcnt += 1 self.tablewidget.insertrow(self.tablerowcnt) def openmsg(self): file,ok = qfiledialog.getopenfilename(self,"打开记录表","c:/",".txt") def getrhandt(self): if self.threadcomid == 0: self.showmsgbox('请先连接串口') else: data,ok = qinputdialog.gettext(self, "露点仪数据", "按如下格式记录：\n rh空格t\n示例：\n rh(0~100):66.6\n t(0~200):9.8\n 输入：66.6 9.8", qlineedit.normal, "66.6 9.8" ) if ok == true: data = re.findall('^[0-9]+\.[0-9]+\s+[0-9]+\.[0-9]+$', data.rstrip()) if len(data) == 0: self.showmsgbox('数据格式有误，重新录入') else: data = data[0].split() print(data) self.datadict['rhldy'] = data[0] self.datadict['tldy'] = data[1] if self.getmcudata() is none: return none print(self.datadict) self.inserttablenewline() else: self.showmsgbox('请重新录入数据') def showmsgbox(self,strtoshow): qmessagebox.warning(self,'提示',strtoshow,qmessagebox.ok) def savemsg(self): file,ok = qfiledialog.getsavefilename(self,"保存记录表","c:/",".txt") def scomautofind(self): self.pushbutton.setdisabled(true) self.scomlist = list(serial.tools.list_ports.comports()) if len(self.scomlist) <= 0: self.showmsgbox('未发现串口，请检查线缆连接') self.pushbutton.setdisabled(false) else: comnum = len(self.scomlist) print(str(comnum) + 'scom is found') while comnum: comnum = comnum - 1 if "usb" in str(self.scomlist[comnum]): self.threadcomid = serialthread(portname=self.scomlist[comnum][0]) self.threadcomid.start() self.graphicsview.setstylesheet("background-color: rgb(0, 255, 0);") print(str(self.scomlist[comnum]) + ' is added')
由于我用的是rs232转usb接入电脑，设备名称是usb-serial ch340，当然还有其他rs232转usb芯片，如pl2303等。我这里就单独检查usb是否在设备名称中，没有检查全名，这里要根据实际需求变动
最后就是main了，没什么特别
if __name__ == "__main__": app = qapplication(sys.argv) myshow = mywindow() myshow.show() print('程序终止') sys.exit(app.exec_())
看一下实际运行效果：
实际运行，（忽略 添加数据 与 数据记录表….）
点击connect后，
当然点击添加数据也是没问题的哈
奉上全部工程文件，链接如下：
https://download.csdn.net/download/ysgjiangsu/10324162
以上就是python之pyqt多线程串口代码分析的详细内容。