Avoid dependant event trigger each other - excel

Question

I have a Worksheet_change in which two events are checked (edits on cells of column C and edits on cells of column D). The problem is that an edit on column C's cells modify the value of column D's cells (and viceversa), so the Worksheet_change is triggered repeatedly and excel eventually crashes.
How can I avoid the problem but maintaining my functionality?
Private Sub Worksheet_Change(ByVal Target As Range)
Dim rgFound As Range
Dim defVal As Range
Dim currParam As Range
Dim currParamDict As Range
Set targ = Intersect(Target, Range("A:A"))
If Not targ Is Nothing Then
With Worksheets("FT_CASE_xx")
For Each defVal In .Range("A2", .Range("A" & Rows.Count).End(xlUp)).Offset(, 1)
Set currParam = defVal.Offset(, -1)
Dim xlFirstChar As String
xlFirstChar = Left$(currParam, 1)
If xlFirstChar = "B" Then
Set rgFound = Worksheets("DEF_BOOLEAN").Range("A:A").Find(currParam.value)
defVal.Offset(, 1).Interior.Color = RGB(230, 230, 230)
defVal.Offset(, 1).Locked = True
defVal.Offset(, 2).Select
With Selection.Validation
.Delete
.Add Type:=xlValidateList, AlertStyle:=xlValidAlertStop, Operator:=xlBetween, Formula1:="TRUE,FALSE"
.IgnoreBlank = True
.InCellDropdown = True
.InputTitle = ""
.ErrorTitle = ""
.InputMessage = ""
.ErrorMessage = ""
.ShowInput = True
.ShowError = True
End With
Else
Set rgFound = Worksheets("DEF_FLOAT").Range("A:A").Find(currParam.value)
defVal.Offset(, 1).Interior.ColorIndex = 0
defVal.Offset(, 1).Locked = False
defVal.Offset(, 2).Locked = False
defVal.Offset(, 1).NumberFormat = "0.000"
defVal.Offset(, 2).NumberFormat = "0.000"
defVal.Offset(, 3).NumberFormat = "0.000"
End If
If rgFound Is Nothing Then
Debug.Print "Name was not found."
Else
If xlFirstChar = "B" Then
Set currParamDict = rgFound.Offset(, 3)
Else
Set currParamDict = rgFound.Offset(, 5)
End If
defVal.value = currParamDict.value
End If
Next defVal
End With
Else
Set targ = Intersect(Target, Range("C:C"))
If Not targ Is Nothing Then
Dim coeffVal As Range
Dim currVal As Range
Dim RequestedVal As Range
With Worksheets("FT_CASE_xx")
For Each coeffVal In .Range("C2", .Range("C" & Rows.Count).End(xlUp))
Set currVal = coeffVal.Offset(, -1)
Set RequestedVal = coeffVal.Offset(, 1)
Set ParamName = coeffVal.Offset(, -2)
Dim xlFirstChar2 As String
xlFirstChar2 = Left$(ParamName, 1)
If ((xlFirstChar2 = "F") And (IsEmpty(coeffVal.value) = False)) Then
RequestedVal.value = coeffVal.value * currVal.value
End If
Next coeffVal
End With
Else
Set targ = Intersect(Target, Range("D:D"))
If Not targ Is Nothing Then
Dim coeffsVal As Range
Dim val As Range
Dim reqVal As Range
Dim Parameter As Range
With Worksheets("FT_CASE_xx")
For Each reqVal In .Range("D2", .Range("D" & Rows.Count).End(xlUp))
Set coeffsVal = reqVal.Offset(, -1)
Set val = reqVal.Offset(, -2)
Set Parameter = reqVal.Offset(, -3)
Dim xlFirstChar3 As String
xlFirstChar3 = Left$(Parameter, 1)
If ((xlFirstChar3 = "F") And (IsEmpty(reqVal.value) = False)) Then
If val.value = 0 Then
coeffsVal.value = reqVal.value
Else
coeffsVal.value = reqVal.value / val.value
End If
End If
Next reqVal
End With
Else
Exit Sub
End If
End If
End If
End Sub
Maybe a different management of target intersection? How?

Answer 1

My favoured method (which can also be useful in other situations) is to create a variable at global or module level (as required) then check this on each run of the code
Private disableEvents as Boolean
Private Sub Worksheet_Change(ByVal Target As Range)
If disableEvents Then Exit Sub
disableEvents=True
<code here>
disableEvents=False
End sub