GS1-128 barcode parsing

Scanner Model :- Motorola- DS4208-HC

We need to parse the GS1-128 barcode. We know they are going to use GTIN(01), lot number(10), Expiration date(17), serial number (21). Input String:- (01)07612345678900(17)100503(10)AC3453G3(21)455777

The problem is that barcode reader outputs a string, the format is like this:

01076123456789001710050310AC3453G321455777

Since there is not a separator and both serial number and lot number are a variable length according to GS1 standard, we have trouble to identify the segments.

There should be a FNC1 character at the end of a variable-length field that is not filled to maximum; so that FNC1 will appear between the G3 and the 21. what I have read is NC1 is invisible to humans but can be detected by scanners and will be reproduced in the string reported by the scanner. Simply send the string directly to a text file and examine the text with a hex reader. The FNC1 should be obvious. But we are still not able to read FNC1 in the reader.