ST25DV64KC - Fast Read Single Block

[selvaraj_velayutham]

I am developing an Android app to read values from the NFC-v tag (ST25DV64KC). To revalidate my implementation, I am using the ST25 TAP app and then sending a custom command to test the commands according to the data sheet (ST25DV64KC). From an Android device, I am not able to test the commands related to the fast transfer mode. Whichever command I send with the fast feature (like FastReadSingleBlock), the response is a "Tag not in the field" error. Whereas if other commands like "Read single block" or "Read configuration" execute, the command returns the value with success. The command I am using for FastReadSingleBlock is 01 C0 02 00. Could you please help me to find the proper command to execute the fast features? In the end, I would to send the text or any file via FTM.

[Brian TIDAL]

Hi,

see Solved: ST25DV NFC Android App fastReadMailboxMessage and ... - STMicroelectronics Community for similar question about fast commands.

If you plan to use the FTM, you can use the 26kbps commands such as readMailboxMessage.

Rgds

BT

[selvaraj_velayutham]

Hello Brian,

Thank you for the quick reply.

May I know the technical reason why I have to use readMailboxMessage, instead of FTM functions for Android devices? One of the main requirements for my project is to send files by using FTM. If I am not able to use this FTM feature via smart devices either by Android or iOS devices, I need a strong explanation to modify the requirements.

Thank you in advance for your detailed explanation,

Best Regards,

Selvaraj

[JL. Lebon]

Hello, 

Please do not confuse Fast Transfer Mode and Fast commands.

FTM is a mechanism that uses the internal RAM buffer of the ST25DV to transfer data between an NFC reader and an MCU. It is called "Fast" transfer because it is much faster than transferring data through the EEPROM (as the write time into the buffer is almost immediate when EEPROM write time is several ms).

"Fast" commands are command that have a response data rate of 53kb/s instead of the standard NFC Type5 26kb/s.
For each "standard" read command, there is an equivalent in "Fast" data rate. For example, the Read Message command (26kb/s) as an equivalent at 56kb/s: Fast Read Message.

To do FTM, you can use either the "standard" data rate commands or the "fast" data rate commands.

Unfortunately, smartphones do not support data rates higher than 26kb/s, so they don't support "Fast" data rate commands (only NFC readers do).

So, if you are using a smartphone, you can do FTM, but using the 26kb/s commands, that are: Read Message. Write Message commands and not the Fast Read Message and Fast Write Message commands. The data rate is 26kb/s, but the FTM functionality is the same.

Best regards.