CR95HF, 64 Bytes Frames

[Enrico Tmiello]

Posted on June 19, 2018 at 08:28

Hi, We are Using a CR95HF and we're trying to read a frame of 78 bytes with CR95HFDll_SendReceive but we get in return a 64 bytes frame with CRC and error code CCCCCC.

Is there a way to solve the problem of the limited 64 bytes frame when using USB for the CR95HF?

♯

?

♯

?#cr9hf #64bytes

[NFC/RFID Customer support]

Posted on June 19, 2018 at 11:56

Hi Enrico,

the last firmware revision of the STM32 embedded in the CR95HF board allows to send and receive up to 512 bytes.

This improvement is managed by the DLL used on the PC side and the STM32 firmware from ths CR95HF board.This improvement is transparent for user and fully managed by the STM32/DLL.

New DLL can be found in the last version of CR95HF PC SW (STSW-95HF001 v2.2.0): DLL revision 1.2 supports this improvement.

http://www.st.com/content/st_com/en/products/embedded-software/st25-nfc-rfid-software/stsw-95hf001.html

STM32 firmware can be download in our internet web site (STSW-M24LR007 v3.7.1):

http://www.st.com/content/st_com/en/products/embedded-software/st25-nfc-rfid-software/stsw-m24lr007.html

ST LINK V2 board can be used to update your M24LR-DISCOVERY board.

http://www.st.com/content/st_com/en/products/development-tools/hardware-development-tools/development-tool-hardware-for-mcus/debug-hardware-for-mcus/debug-hardware-for-stm32-mcus/st-link-v2.html

Best regards

NFC/RFID ST support

[Enrico Tmiello]

Posted on June 20, 2018 at 07:54

Hi, Thank you for the answer, the new firmware resolved the 94 bytes problem but reading and writing are a lot worse now, is there any parameter or configuration that might help us?

[NFC/RFID Customer support]

Posted on June 20, 2018 at 10:07

HI,

Can you please specify what is not working well ? The only différences between the previous software and the actual one is that, now, more than 1 USB transaction is used to be able to transfer more than 64 bytes (1 USB transaction for 64bytes, 2 for 94bytes). I don't know if you are using the CR95HF through the PC software or your own developed software. In case of own software, you have to know that, to enable big amount of data transfer(in iso15693 rf protocol, the cr95hf is configured as specific way. So when changing rf protocol from iso15693 to iso1443A for example, you need to add reset_spi commad between. All other rf setting are not changed.

Best regards

NFC/RFID ST support

[Enrico Tmiello]

Posted on June 22, 2018 at 11:48

So we are using ISO 15693, and we are developing our SoftWare, we are using the SendReceive command. When we are putting something in the mailbox and wait  for response,02a02d command, if we use the 02A8 for the frame length, most of the time we get 0045 or 8E00: reception lost without end of file received, even with short frames,  and we have the 64 byte problem when we don't use 02A8.

Is there a specific series of command that needs to be used? When should we use the 02A8 command?

[NFC/RFID Customer support · Accepted solution]

Posted on June 22, 2018 at 17:17

Standard use or 02A8 command doesn't change ISO15693 RF protocol configuration. The only adjustment you can try to improve tag answer reception is to use 100% modulation (CR95HFDLL_SELECT, 0109

)

instead of 10% (CR95HFDLL_SELECT, 010D). I suppose that '0045' is the expected data to be received. 8E00 is an answer from CR95HF IC, it means that the communication has noise and the tag answer cannot be decoded successfully, the coupling between tag & reader is not the better one. Also, I don't understand ,02a02d command.

Best regards

NFC/RFID ST support