Casio QT-6600 Reference Manual page 152

Registration
Add on code
Multi EAN link
R-148
QT-6600 has a capavility to log the supplemental (add-on) barcode data with main
barcode.
The add-on code is logged to the Add on/ VMP file (file-040) with main barcode, shop
code, consecutive number, date, time and item quantity.
The barcode data of the main item should be programmed to the Non PLU table.
Shop code is programmed to the 48-th record of the general control file.
If you want to register an item as the item with different barcode data, program the barcode
data of the linked item and the parent item to the multi EAN link file (file no. = 075).
Refer to 4-4-3 Programming multi EAN link of the programming manual.