Creating a 6131 readable external tag wth an external reader

[gngulrajani]

Hello All,

I am trying to create a 6131 readable NFC tag using an external reader.
Currently I have an application that writes a correctly formatted NDEF/Mifare message into Logical block 4-6 (see below) of a 1k Mifare tag.

The problem I am having is writing a usable '6131' key to the tag.

I have tried the following things to make my tag readable by a 6131:

I have tried copying the sector trailer from a 6131 written tag which looks like

Sector X / Block 3
 00 00 00 00 00 00 7F 07 88 40 00 00 00 00 00 00

The interesting thing is that I do not see the 'd3 f7 ...' key written there. Is the Key-A stashed somewhere else?

I have tried producing a sector trailer with the 'd3 f7 ...' key in the Key-A position to no avail as well.

Sector X / Block 3
 d3 f7 d3 f7 d3 f7 7F 07 88 40 00 00 00 00 00 00

I have seen that when 6131 initializes Sector 0 / Block 1 with a MAD block. I attempted to write that into my tag as well

Sector:0 Block: 1
EB 01 03 E1 00 00 00 00 00 00 00 00 00 00 00 00

Can anybody give me any tips about how to properly initialize a Mifare tag so a 6131 can read it ?

Thanks in advanced for any tips!
-best
-greg



Below is a dump of the tag I am currently generating:

Sector:0
Block:0

 14 25 0B E2 D8 88 04 00 47 C1 24 57 C1 00 08 06
    %     ?  ?  ?        G  ?  $  W  ?

Sector:0
Block:1

 EB 01 03 E1 00 00 00 00 00 00 00 00 00 00 00 00
 ?        ?

Sector:0
Block:2

 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

Sector:0
Block:3

 00 00 00 00 00 00 FF 07 80 69 00 00 00 00 00 00
                   ?     ?  i
Sector:1
Block:0

 03 27 D1 01 23 55 03 38 31 2E 31 33 38 2E 34 2E
    '  ?     #  U     8  1  .  1  3  8  .  4  .

Sector:1
Block:1

 39 39 2F 41 42 43 2F 6D 65 64 69 61 2F 74 68 65
 9  9  /  A  B  C  /  m  e  d  i  a  /  t  h  e

Sector:1
Block:2

 5F 66 61 6C 6C 2E 61 73 70 3F 00 00 00 00 00 00
 _  f  a  l  l  .  a  s  p  ?

Sector:1
Block:3

 00 00 00 00 00 00 FF 07 80 69 00 00 00 00 00 00
                   ?     ?  i

[jlanza]

Did you get it working?