在做自動(dòng)化工程項(xiàng)目時(shí)常常需要用上位機(jī)對(duì)PLC進(jìn)行監(jiān)控，如果是大的工程項(xiàng)目可以使用組態(tài)軟件來(lái)完成，但對(duì)中小項(xiàng)目為了節(jié)約成本，可以采用自己寫(xiě)上位機(jī)程序來(lái)完成對(duì)PLC的監(jiān)控。
海為提供了一個(gè)海為PLC的通訊控件，通過(guò)這個(gè)控件實(shí)現(xiàn)上位機(jī)與海為PLC之間的通訊十分方便，它封裝了Modbus通訊協(xié)議和HaiwellBus協(xié)議，以點(diǎn)的形式實(shí)現(xiàn)對(duì)海為PLC的數(shù)據(jù)訪問(wèn)，對(duì)每個(gè)點(diǎn)可以定義它的名稱/數(shù)據(jù)類型/小數(shù)長(zhǎng)度/點(diǎn)注釋等，不必去了解Modbus通訊協(xié)議和HaiwellBus協(xié)議的具體內(nèi)容，只要有上位機(jī)編程經(jīng)驗(yàn)就可以完成。
窗口1的程序如下：
Option Explicit
'啟動(dòng)跑馬燈按鈕
Private Sub Command1_Click()
'啟動(dòng)跑馬燈，M0置1，點(diǎn)序號(hào)30
HWPLCComm1.HWPLCs(1).SetPointValue 30, 1
End Sub
'停止跑馬燈按鈕
Private Sub Command2_Click()
'停止跑馬燈，M1置1，點(diǎn)序號(hào)31
HWPLCComm1.HWPLCs(1).SetPointValue 31, 1
End Sub
'啟動(dòng)采樣按鈕
Private Sub Command3_Click()
' HWPLCComm1是海為PLC通訊控件名稱，Timer1是畫(huà)面刷新定時(shí)器
HWPLCComm1.Run Not HWPLCComm1.RunFlag
Timer1.Enabled = HWPLCComm1.RunFlag
If HWPLCComm1.RunFlag Then
Command3.Caption = "停止采樣"
Shape2.FillColor = vbGreen ‘采樣指示燈綠色
Else
Command3.Caption = "啟動(dòng)采樣"
Shape2.FillColor = vbWhite ‘采樣指示燈紅色
End If
End Sub
'窗口1裝載
Private Sub Form_Load()
Dim i As Long
'添加1臺(tái)PLC，PLC地址為1，名稱為“1號(hào)PLC”
HWPLCComm1.HWPLCs.AddPLC 1, "1號(hào)PLC"
'在“1號(hào)PLC”下增加采樣點(diǎn)
For i = 0 To 15
HWPLCComm1.HWPLCs(1).AddPoint "y" & i '增加采樣點(diǎn)Y0-Y15
Next i
'在“1號(hào)PLC”下增加其他離散的采樣點(diǎn)
HWPLCComm1.HWPLCs(1).AddPoint "sv0", , "當(dāng)前掃描時(shí)間 單位0.1ms"
HWPLCComm1.HWPLCs(1).AddPoint "sv1", , "最小掃描時(shí)間 單位0.1ms"
HWPLCComm1.HWPLCs(1).AddPoint "sv2", , "最大掃描時(shí)間 單位0.1ms"
HWPLCComm1.HWPLCs(1).AddPoint "sv12", "Year", "年"
HWPLCComm1.HWPLCs(1).AddPoint "sv13", "Month", "月"
HWPLCComm1.HWPLCs(1).AddPoint "sv14", "Day", "日"
HWPLCComm1.HWPLCs(1).AddPoint "sv15", "Hour", "時(shí)"
HWPLCComm1.HWPLCs(1).AddPoint "sv16", "Minute", "分"
HWPLCComm1.HWPLCs(1).AddPoint "sv17", "Second", "秒"
HWPLCComm1.HWPLCs(1).AddPoint "sv18", "Week", "星期"
HWPLCComm1.HWPLCs(1).AddPoint "sm3", , "10ms時(shí)鐘脈沖"
HWPLCComm1.HWPLCs(1).AddPoint "sm4", , "100ms時(shí)鐘脈沖"
HWPLCComm1.HWPLCs(1).AddPoint "sm5", , "1s時(shí)鐘脈沖"
HWPLCComm1.HWPLCs(1).AddPoint "m0", "Start", "跑馬燈啟動(dòng)"
HWPLCComm1.HWPLCs(1).AddPoint "m1", "Stop", "跑馬燈停止"
HWPLCComm1.HWPLCs(1).AddPoint "v0"
HWPLCComm1.HWPLCs(1).AddPoint "v2"
HWPLCComm1.HWPLCs(1).AddPoint "v100", , "實(shí)數(shù)例子", [REAL ] '實(shí)數(shù)類型為5
HWPLCComm1.HWPLCs(1).AddPoint "ccv50", , "32位計(jì)數(shù)器"
HWPLCComm1.HWPLCs(1).AddPoint "ccv100", , "16位計(jì)數(shù)器"
'將點(diǎn)加到Listview中顯示, Y0-Y15 16個(gè)點(diǎn)不加入，用指示燈來(lái)顯示狀態(tài)
Dim Newitem As ListItem
For i = 17 To HWPLCComm1.HWPLCs(1).PointCount
Set Newitem = ListView1.ListItems.Add(, , i)
Newitem.SubItems(1) = HWPLCComm1.HWPLCs(1).iPoints(i).PointAddress
Newitem.SubItems(2) = HWPLCComm1.HWPLCs(1).iPoints(i).PointName
Newitem.SubItems(4) = HWPLCComm1.HWPLCs(1).iPoints(i).PointNote
Next i
'將PLC地址和名稱用標(biāo)簽顯示
Label3(0) = HWPLCComm1.HWPLCs(1).PLCAddress
Label3(1) = HWPLCComm1.HWPLCs(1).PLCName
'將16只指示燈的標(biāo)簽以點(diǎn)名稱顯示（Y0~Y15）
For i = 1 To 16
Label1(i - 1) = HWPLCComm1.HWPLCs(1).iPoints(i).PointName
Next i
End Sub
'雙擊列表中的點(diǎn)打開(kāi)窗口2，對(duì)該點(diǎn)的值進(jìn)行修改
Private Sub ListView1_DblClick()
Dim i As Long
If Not ListView1.SelectedItem Is Nothing Then
i = ListView1.SelectedItem.Index + 16
Form2.vPointIndex = i
Form2.Caption = "寫(xiě)入值 " & HWPLCComm1.HWPLCs(1).iPoints(i).PointName
Form2.Label1.Caption = "寫(xiě)入值 " & HWPLCComm1.HWPLCs(1).iPoints(i).PointName & "："
Form2.Text1 = HWPLCComm1.HWPLCs(1).iPoints(i).PointValue
Form2.Show 1
End If
End Sub
' Timer1是畫(huà)面刷新定時(shí)器
Private Sub Timer1_Timer()
'刷新值
Dim i As Long
'刷新Y0-Y15值
For i = 1 To 16
If HWPLCComm1.HWPLCs(1).iPoints(i).PointValue = 1 Then
Shape1(i - 1).FillColor = vbRed '值=1，為真
Else
Shape1(i - 1).FillColor = vbWhite '值=0，為假
End If
Next i
'刷新其他點(diǎn)值
For i = 17 To HWPLCComm1.HWPLCs(1).PointCount
ListView1.ListItems(i - 16).SubItems(3) = HWPLCComm1.HWPLCs(1).iPoints(i).PointValue
Next i
End Sub
窗口2的程序如下：
Option Explicit
Public vPointIndex As Long '公共變量，存儲(chǔ)被雙擊點(diǎn)的序號(hào)
'確定按鈕
Private Sub Command1_Click()
If Text1.Text = "" Then Exit Sub
'按確定，則寫(xiě)入點(diǎn)的值
Form1.HWPLCComm1.HWPLCs(1).SetPointValue vPointIndex, Text1.Text
Unload Me
End Sub
'取消按鈕
Private Sub Command2_Click()
Unload Me
End Sub
Private Sub Text1_GotFocus()
Text1.SelStart = 0
Text1.SelLength = Len(Text1)
End Sub
Private Sub Text1_KeyPress(KeyAscii As Integer)
If KeyAscii = 13 Then
Command1_Click
End If
End Sub
運(yùn)行結(jié)果如下圖：
