You a looking for something like that?
Option Explicit
Public FromMacro As Boolean
Sub X()
FromMacro = True
Call MacroX
End Sub
Sub MacroX()
Dim Iteration As Long
Dim i As Long
If FromMacro = True Then
Iteration = 1
Else
Iteration = 100
End If
For i = 1 To Iteration
MsgBox Iteration
Next i
FromMacro = False
End Sub