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Extended Read Multiple Blocks (Android NfcV)

DMugg.1
Associate II

I need to read multiple blocks of the ST25DV64K-I.

For example 178 Blocks starting from 1D.

UID: E0 02 26 00 A7 3B 33 B6

My command:

22 33 B6 33 3B A7 00 26 02 E0 1D B2

I only get 01:02.

What's wrong with my command?

1 ACCEPTED SOLUTION

Accepted Solutions
Brian TIDAL
ST Employee

Hi,

the proper coding of the Extended read Multiple Blocks is:

  • request flags: 8 bits
  • 33h
  • UID( when address_flag = 1): 64 bits
  • first block number: 16 bits
  • Number of blocks: 16 bits

So, 2 bytes are missing in your command.

Rgds

BT

In order to give better visibility on the answered topics, please click on Accept as Solution on the reply which solved your issue or answered your question.

View solution in original post

6 REPLIES 6
Brian TIDAL
ST Employee

Hi,

the proper coding of the Extended read Multiple Blocks is:

  • request flags: 8 bits
  • 33h
  • UID( when address_flag = 1): 64 bits
  • first block number: 16 bits
  • Number of blocks: 16 bits

So, 2 bytes are missing in your command.

Rgds

BT

In order to give better visibility on the answered topics, please click on Accept as Solution on the reply which solved your issue or answered your question.
DMugg.1
Associate II

Oh right of course so it gets: 22 33 B6 33 3B A7 00 26 02 E0 1D 00 B2 00

The maximum Blocks should be 2047? But I can't read my 178 Blocks.

I now just get the I/O failure...

Thanks for your help.

DM

Brian TIDAL
ST Employee

Hi,

can you share more information about the I/O failure? Android failure or tag failure?

I don't know the physical limits on Android when transceiving NFC data and that may be the cause of this failure. What about sending 6 x Extended Read Multiple blocks (32 blocks)?

Rgds

BT

In order to give better visibility on the answered topics, please click on Accept as Solution on the reply which solved your issue or answered your question.
DMugg.1
Associate II

You are right...

The limit is 64 as it seems.

65 number of Blocks just get rejected...

Brian TIDAL
ST Employee

Hi

this limit is an Android limit.

ST25DV64K-I accepts up to NumOfBlocks=2047.

Rgds

BT

In order to give better visibility on the answered topics, please click on Accept as Solution on the reply which solved your issue or answered your question.
DMugg.1
Associate II

Yea that's kinda sad..

So I have to make multiple requests for the same number of blocks...