ST25TV UID

[Luke_abc]

Hi,

Is it possible to understand the TAG variant from the UID during the inventory ?
For example, ST25TV16K has the UID as shown below:

 

For ST25TV02K, the UID is as shown below:

If you see the above snapshots, ST product code is 48h for ST25TV16K and 23h for ST25TV02K. Are these values fixed and can we identify the tags from the product code ? Is the product code 48h  same for ST25TV64K also ? Could you also please tell what does the IC Mfg code say about the tags ?

The reason I am asking is, If I know the tag, I can know which are the supported commands for specific tags. 
For example: Extended get system info is not supported in ST25TV02K, but supported in ST25TV16K.

@Brian TIDAL 

 

[JL. Lebon]

Hello, 

Yes, you can identify the tag from the Product Code byte in the UID byte 5.
This byte is fixed for each type of tag. Its goal is exactly what you want to do, which is identifying a tag type to know what commands it supports. All devices sharing the same Product code also share the same command set.

You can also use the ICRef to achieve the same goal. Difference between ICRef and Prodcut code is that Prodcut code (when different from ICRef) provides little bit more information and is more "accessible" since it is provided during the inventory.

Product code 48h is for both ST25TV16K and ST25TV64K because both tags are supporting the same command set.

If you need to differentiate between ST25TV16K and ST25TV64K you need to use the Extended Get System Info to retrieve the memory size (which is the only difference between those two versions).

Best regards.

[Brian TIDAL]

Hi,

the IC Mfg code is a code identifying the manufacturer of an IC device. 02h is the code for STMicroelectronics.

I guess you would like to identify the tag not only for supported commands list but also to retrieve the Mem size of the tag. The Mem Size can be retrieve in the response from the Get System Information. Unfortunately, the coding of the Mem size in the Get System Information is limited to 1 byte for the number of blocks and this field cannot be used for device having more that 256 blocks (thus this field is not present in the response for such devices). The Extended Get System Information has been added in the ISO15693 standard to be able to provide memory size information for devices having up to 65,536 blocks. Both Get System Information (2Bh) and Extended Get System Information (3Bh) are defined as optional by the ISO15693.

ST25TV16K and ST25TV64K support Extended Get System Information command in addition to Get System Information command (but the Mem size field is absent in the Get System Information response from those devices).

The IC Ref. is also present in the Get System Information response and Extended Get System Information response (when requested in the Parameter request field).

The Extended Get System Information response can also provide the list of supported command.

Rather than relying on the IC ref., one can send the Get System Information command. If the response includes the Mem size field, this can be used for further memory read/write operation. If the Mem size field is not included, the Extended Get System Information command can be sent to retrieve the Mem size and the list of supported commands.

Can you provide more information on the specific commands you would like to use? Note that sending Extended Get System Information to a ST25TV02K is not an issue: "Command not supported" is simply returned.

Rgds

BT

 

 

[Luke_abc]

Thanks for the perfect answers @Brian TIDAL  and @JL. Lebon .

Which commands are mandatory under ISO15693, and which are optional ? Where to find these information ?

[JL. Lebon]

Hello, 

There are 3 categories of commands defined in ISO15693:
Mandatory commands, optional commands and custom commands.

Actually, only two commands are mandatory in ISO15693: inventory and stay quiet.
All other commands are optional (but off course almost all ISO15693 tags implement at least the read and write single block commands).

This information is found in the IEC/ISO15693-3 specification (which is not a free documentation unfortunately).

Best regards.