GS1 AI syntax with GS separators

[xjpf]

How to make 4-square datamatrix from this line?
0102900285850353215EtQT"cSm,oH1�91EE09�92/kklRSOz6PDV69t9tX6Rmh+zmIx01fCo+2FZVYbAyd4=
Should look like this:

(but this one doesnt have fnc1)

[xjpf]

Tried to split input data like this:
gtin = '02900285850353'
smth = 'EE09'
serial = '5EtQT"cSm,oH1'
tail= '/kklRSOz6PDV69t9tX6Rmh+zmIx01fCo+2FZVYbAyd4='
data=f"(01){gtin}(21){serial}(91){smth}(92){tail}"

Got 4-square datamatrix, but now other problem:
ALL delimeters are FNC1, while need those GS (''�"-bytes)

Is it possible to pass GS?

[terryburton]

Your initial symbol is malformed since it does not contain FNC1 in first character position which required for GS1 Data Matrix barcodes (i.e. containing AI element string syntax).

What you require is to use the gs1datamatrix encoder with the input (01)02900285850353(21)5EtQT"cSm,oH1(91)EE09(92)/kklRSOz6PDV69t9tX6Rmh+zmIx01fCo+2FZVYbAyd4=.

BWIPP will generate a symbol that contains FNC1 separators within the internal data, as this is the correct (canonical) thing to do. Readers shall pass the FNC1 separator codewords as GS characters to the host.

[xjpf]

Sorry forgot to mention, that I'm using exactly gs1datamatrix encoder
And if you scan generated picture I've added, you'll find out that there is 3 FNC bytes: one as header and two as delimiters.
And I need it only for header. Delimiters should be GS, not FNC1

[terryburton]

The use of the GS character as an element separator is tolerated precisely because the host on the receiving end of the transfer protocol is unable to differentiate between FNC1 and GS.

Nevertheless, FNC1 is the the canonical separator and BWIPP will not allow you to do otherwise without manually driving the encoding using the regular datamatrix encoder with the parse and parsefnc options:

^FNC10102900285850353215EtQT"cSm,oH1^GS91EE09^GS92/kklRSOz6PDV69t9tX6Rmh+zmIx01fCo+2FZVYbAyd4=

However, this method is error prone. So my advice is to leave it to BWIPP to do the right thing.