Macro to Auto populate master worksheet

Ok guys, I have a workbook set up with six sheets and a macro to compile them into a master sheet, making seven total. What i would like to do is have it set up where when any information is entered into one of the six sheets it is automatically updated in the master sheet. The sheet titles are BPU1, BPU2, BPU3, BPU4, BPU8, and BPU9. The master sheet will be titled master. Each of the six sheets are formatted in the same way with these following column headings (17 total).
Date, Cell, Type, Shift, Clock #, Setup, Down Maint, Inspection, Scrap/Rework, No Material, Operator Unavailable, Cycle Time Issues, Break, Sunk/Lost Time, Troubleshooting, Machine Running, and total.
The rows will be updated with hundreds of entries per day per sheet. The macro i am currently using to create the master sheet is as follows.

Sub CopyFromWorksheets()
Dim wrk As Workbook 'Workbook object - Always good to work with object variables
Dim sht As Worksheet 'Object for handling worksheets in loop
Dim trg As Worksheet 'Master Worksheet
Dim rng As Range 'Range object
Dim colCount As Integer 'Column count in tables in the worksheets

Set wrk = ActiveWorkbook 'Working in active workbook

For Each sht In wrk.Worksheets
If sht.Name = "Master" Then
MsgBox "There is a worksheet called as 'Master'." & vbCrLf & _
"Please remove or rename this worksheet since 'Master' would be" & _
"the name of the result worksheet of this process.", vbOKOnly + vbExclamation, "Error"
Exit Sub
End If
Next sht

'We don't want screen updating
Application.ScreenUpdating = False

'Add new worksheet as the last worksheet
Set trg = wrk.Worksheets.Add(After:=wrk.Worksheets(wrk.Worksheets.Count))
'Rename the new worksheet
trg.Name = "Master"
'Get column headers from the first worksheet
'Column count first
Set sht = wrk.Worksheets(1)
colCount = sht.Cells(1, 255).End(xlToLeft).Column
'Now retrieve headers, no copy&paste needed
With trg.Cells(1, 1).Resize(1, colCount)
.Value = sht.Cells(1, 1).Resize(1, colCount).Value
'Set font as bold
.Font.Bold = True
End With

'We can start loop
For Each sht In wrk.Worksheets
'If worksheet in loop is the last one, stop execution (it is Master worksheet)
If sht.Index = wrk.Worksheets.Count Then
Exit For
End If
'Data range in worksheet - starts from second row as first rows are the header rows in all worksheets
Set rng = sht.Range(sht.Cells(2, 1), sht.Cells(65536, 1).End(xlUp).Resize(, colCount))
'Put data into the Master worksheet
trg.Cells(65536, 1).End(xlUp).Offset(1).Resize(rng.Rows.Count, rng.Columns.Count).Value = rng.Value
Next sht
'Fit the columns in Master worksheet
trg.Columns.AutoFit

'Screen updating should be activated
Application.ScreenUpdating = True
End Sub



I am a complete VBA novice and that code is one that i copied off of a website. Let me know if you have any more questions and thanks for the help