Write Tag (Write Block) problems

[portmankim]

This App is cool, I can use it to read some Mifare 1K tags I have here.
I'm using a new Huawei P8 Lite mobile phone, works fine...except:

• I can read all data from Tags, fast and precise
• I can write data to a Tag via Write Dump (Clone), by selecting 1 Sector a time
• but I can't write data using Write Tag -> Write Block:
• * when using Write Block the App says: "Data Succesfully Written" ..but nothing
• * when I read back the Tag no data has changed
• * the Tags are empty (from manufacturer, all keys are FFFF...)
• * as said before, via Write Dump the data does change on the Tags!!!

What am I doing wrong?
Kim

[ikarus23]

Hi Kim,

this is really strange. What Android version is in use? Do you have another NFC enabled phone to check if there is the same issue?

[psg69]

Same problem here.
Samsung Galaxy S5...

[psg69]

And when it does write via "Write Dump" it is stuffing up and destroying access to all blank sectors...

[nestornino]

Hi, I'm currently developing an application to write NFC tags, but have a problem when I want to make writing with keys. Reviewing the code Available Project, found in WriteTag.java something I do not understand. The WriteBlock operation (lines 485 and 492), it has arguments that do not match those of the android developers page, which are an integer and a byte just:
http:https://developer.android.com/intl/es/reference/android/nfc/tech/MifareClassic.html#

I am new to these issues, but I would help her answer.
Thank you

[ikarus23]

Hi, the writeBlock() you see is not the function from the Android API. It is the writeBlock() of the MCReader (part of MCT). I hope this helps.

[ikarus23]

Any news on that?

[nestornino]

Hello, I discovered that the problem was caused because the documentation for Android developers said that for writing to each block, the numbering of each sector was restarted, and I was trying to write in block manufacturer, so it was the error.

I finished the application, but I put aside, because I want to establish a business model through sale tag in my country.

Thanks for asking about my project.

[ikarus23]

Lacking feedback of OP. Closed.