ST25dv64KC: how to use Fast Extended Read Multiple Blocks?

[Greidimar]

I'm using ST25dv64KC memory and need to use Fast Extended Read Multiple Blocks C5h, but I haven't had any success.

I'm passing the sequence "22C502E00251678F057ABB000001F00"

22 - request flags
C5 - Fast Extended Read Multiple Blocks
02 - IC mfg code
XXXXXXXXXXXXXXX - my UID
0000 - starting block
1F00 - ending block

[Andrew Neil]

Have you established basic comms with the memory?

[Greidimar]

I already read and write to the ST25dv64KC memory using Extended Read Single Block - 30h and Extended Write Single Block - 31h.

I enter the memory password and then read.

But I want to make it faster, and the Fast Extended Read Multiple Blocks - C5h command doesn't work.

I use the Flutter NFC Kit library.

[JL. Lebon · Accepted solution]

Hello, 

The Fast commands use a doubled data-rate for the tag-to-reader transmission.
This doubled data-rate is not supported by smartphones as of today. Only RFID readers can receive double data-rate responses.
So, if you are using a smartphone, you will not be able to use the Fast commands.
if you are using a RFID reader, you must inform the reader to listen for a double data-rate answer, otherwise it will not understand the answer.

Best regards.

[Greidimar]

I use Android and iPhone smartphones so it won't work?

[JL. Lebon]

Yes, unfortunately it is not supported by Android phones and iPhones. Only standard high data-rate is supported by those (26kb/s). You can use the Extended read multiple blocks command but not the Fast extended read multiple blocks command.

Best regards.