During flashing Tegra T20 I get the message to enter serial number. The barcode label shows
Col Tegra 2
However I should enter a 16 digit number !?
Problem solved: I have a second T20 where I could read the number and use it for this module.
You can get additional information about Serial N here - https://www.toradex.com/community/questions/15647/cant-find-productidserialno.html