Java Question Adding new functionalities and tags decoding to NFC library

Lectos

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Hello @jjcc

I'm using 1.25 version NFC library and it's working ok. I'm reading the UID from a Mifare Classic 1K Card using "GeTagtUID", but I'm not receiving the complete UID. The last part is missing. The data I get is "59269D35" in hexadecimal, but it would be "59269D35D7". I think the UID of Mifare Classic 1K is 7 or 11 byte long.
Can you please help me to solve this issue?

Thanks in advance.
 

paolofi

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For this specific app, I believe you need to put a file "tech_filter.xml" into the directory "$yourworkingdir/Objects/res/xml" and make it read only. Here's a sample file, you can copy it to your directory.

B4X:
Parsing code.                           0.03
Compiling code.                         0.27
Compiling layouts code.                 0.02
Generating R file.                      Error
AndroidManifest.xml:36: error: Error: No resource found that matches the given name (at 'resource' with value '@xml/tech_filter').


If I put this file in the "....\UltraLightReader\Objects\res\xml\" I receive the same error and the file .XML in the directory is deleted (!?).
Some ideas?

Thanks
 

wildfandango

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Hi all.

I'm using 1.25 version BUT when i use the library the version showed is 1.00 and the list of functions appear to be incomplete?

how i can solve this...

thx for all

nfc1.png
nfc2.png
 

wildfandango

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THX! You are right! my bad....

i have an external folder with libs but C:\Program Files (x86)\...) have preference...
 

jjcc

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Hello @jjcc

I'm using 1.25 version NFC library and it's working ok. I'm reading the UID from a Mifare Classic 1K Card using "GeTagtUID", but I'm not receiving the complete UID. The last part is missing. The data I get is "59269D35" in hexadecimal, but it would be "59269D35D7". I think the UID of Mifare Classic 1K is 7 or 11 byte long.
Can you please help me to solve this issue?

Thanks in advance.
I think there are 2 versions of UID: 4 bytes or 7 bytes. There are other data bytes but they are not part of UID. Can you check the documentation from NXP?
 

jjcc

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How can we write Mifare Classic or NTAG using NFC library ?
For Mifare, the function is there called "WriteSector". I didn't write a sample usage though. NTAG writing is not done yet. But if you know Java, you can modify the code I uploaded in Github
 
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