I'm looking for Aztec specifiactin - I know that this is described in
iso standard 24778 and I can buy it, but I haven't any card ... so I
can't buy it ...
I've problem with not generate but _read_ (decode) the code.
I have to decode matrix 91x91 and I've few questions about it :

1. what data is encoded on the 'eye'-edge (I suspect that there is
information about count of codewords, codeword length, polynomial
etc.) and how to encode them ?

2. how to find where data (in the matrix) is begin (I looked on bits
in few matix and data started at different bits) ?

3. how to find where data (in the matrix) is end ?

4. what is matter/sense of special singns ('high-level' encoding) :
    - LL (I think this is Lower Letter - this sign change the coding
to 5 bits)
    - ML (Main Letter ?? means upper letter ?? )
    - DL (I think this is Digital Letter - this sign change the coding
to 4 bits)
    - US ( ??? )
    - BS (??? Border Sign  :) ??)
    - PS ( ??? )
    - other sings : SOH, STX. ETX, EOT, ENQ, ACK, BEL, BS, HT, LF, VT,
FF, CR, ESC, FS, GS, RS, US, DEL (I, of course, know that CR is Carret
Return or DEL is Delete, but I don't know if it matter in decoding
process)

5. where can be a locations/psitins rows/columns - I've seen (first)
it at 9 and at 13 (in matrix 91x91)

6. I've tired to encode a message AaBbCcDdEeFf in the small matrix
15x15 and its look :

000001111010011
001100111011001
01xx00001110x01
01xxxxxxxxxxx10
111xxxxxxxxx100
001xxxxxxxxx011
001xxxxxxxxx000
011xxxxxxxxx100
011xxxxxxxxx111
110xxxxxxxxx111
001xxxxxxxxx001
000xxxxxxxxxx00
010010010100010
101110000101010
100110010001100

and I don't understand it .........

7. I've tired to decode my example matrix 91x91 and it look strange
(first[last] layer ) :

 scrap of message : WwMAAO9CAEECM
00
00
00
00
11 5-bits W (11000) - why message starts here ?
00
0 1 5-bits BS (11111) - I don't know what is this
11
11
01 (positioned row) why it is there ?
00  - strange bits start
00
10
11
10
11 - strange bits end
1 0 5-bits M (01110)
11
10
00  5-bits A (00010)
01
0 0  5-bits A (00010)
 00
 10
10 5-bits O (10000) without positioned row
01 (positioned row) why it is there ?
00
0 1 5-bits DL (11110)
11
10
10 4-bits 9 (1011)
11
11 4-bits UL (1110)
10
00 5-bits C (00100)
10
0 0 5-bits A (00010)
00
10
00 5-bits E (00110) without positioned row
11
01 (positioned row) why it is there ?
0 0 5-bits E (00110)
01
10
00 5-bits C (00100)
10
0 0 5-bits M (01110)
11
10
.....

I hope that You can help me and help me ... :)

Please help .... SOS

Best regards

Robert Cok

ps. sorry for my English - its result of 50 years Soviet occupation :
(.