下载后可任意编辑元件清单名称型号数量（个）单片机AT89S521RS-232 标准串口设计的接口电路MAX2321串口DB91光耦MOC30521双电压比较器LM3931稳压管LM78051变压器220V 转 9V1二极管IN40072三极管90131可控硅BTA081LED 灯发光二极管1灯泡220V 40W 的白炽灯1滑动变阻器100K1光敏电阻LG44162电阻1001330110K51K1150K2电容103110421054电解电容10pF210uF11000uF/25F12200uF/25F1下载后可任意编辑Private Declare Sub Sleep Lib "Kernel32" (ByVal dwMilliseconds As Long)'通信Dim commflag As BooleanDim commstr(0 To 3) As Byte'灯泡状态 true 亮 false 灭Dim lightstate As Boolean'故障指示灯状态 true 亮 false 灭Dim errorledstate As Boolean'联机指示Dim connection As BooleanDim config As String//当点击“联机”按钮时或动其他按钮时，假如计算机和硬件未连接，会出现”端口打开错误”的命令窗口；假如计算机和硬件连接了，会出现”系统已联机”的字样
Private Sub Command1_Click()On Error GoTo out If Not connection ThenMe
MSComm1
CommPort = Me
Combo1
ListIndex + 1 Me
MSComm1
PortOpen = True If Me
MSComm1
PortOpen = False
