RFID U2270B HELP identify transponder and his memory structure

[abukede]

Hi

Im trying to demodulate a tag with a u2270B system from a old industrial printer but my problem is that
I cant identify the tag, it memory structure and the Modulation Encoding(biphase or manchester)
here is a foto from it:




I also have a LA read from the U2270b I/O but I confess that I'm a bit confused...



Thx in advanced

 

[pranam77]

The shown chip looks like a Read and write Mifare chip works on 13.5 mhz. U2270 is a read only Chip dedecated for 125Khz and cannot be used to read or write this particular tag.
Cheers

 

[abukede]

The shown chip looks like a Read and write Mifare chip works on 13.5 mhz. U2270 is a read only Chip dedecated for 125Khz and cannot be used to read or write this particular tag.
Cheers

Hi thx for the answer.

It actually looks like that Mifare that you talk but if you say that they works at 13.5Mhz it cant be... this is the tag that is originally used by the system. And as you state the U2270B only works at 100 kHz to 150 kHz!!!!

Or its possible that Mifare as IC that works at 125 khz???!!! If not this IC must be from another brand...

 

[pranam77]

No..precisely speaking, when we say "mifare" it should and will work on 13.5Mhz and not any other frequency and U2270 cannot read it or write to it.. As i see the tag stucture and the chip inside, it is 99% a mifare tag or may be some other complications i coudnt guess. Similar chips as you have shown here, are used as tickets in Delhi metro, and too now bieng introduced in bangalore metro.
Cheers

 

[abukede]

No..precisely speaking, when we say "mifare" it should and will work on 13.5Mhz and not any other frequency and U2270 cannot read it or write to it.. As i see the tag stucture and the chip inside, it is 99% a mifare tag or may be some other complications i coudnt guess. Similar chips as you have shown here, are used as tickets in Delhi metro, and too now bieng introduced in bangalore metro.
Cheers

Ok thx anyway...

At the first sight they are almost equal but if we take a closer look we can see that they are not...



The only thing that I have sure is that this tag is working is a U2270B system. You can see it the in this schematic draw:



I will continue to try to figure out what is the memory map of that tag...

Thx :wink: