Detailed information on 15693 Inventory timing on PN7462

[matthewrose]

We are working right now to measure latency and trying to improve the value on the PN7462. We are using ‘NfcrdlibEx1_BasicDiscoveryLoop’ example to do so. We are able to read the UUID of multiple ICODE SLIX tags by applying changes suggested by NXP. We tried  ‘NfcrdlibEx1_BasicDiscoveryLoop’ example. Unfortunately the UUID reading delay seems to be very high. We have a requirement to finish reading of at least four tag’s UUID and Data within 300msec. The delay seems to be nearly 1 second with the above example code. Are there any variables or strategies to apply in order to achieve the goal of reading four tags within 300 mS? Using an o-scope we measure the following:

Inventory delay of 4  ICODE SLIX tags  :     360ms

Inventory delay of 4 TI’s ITAG   :                 340ms

Inventory delay of 4 TI’s ITAG tag with same last UUID byte   :     554ms

Thank you very much for your time.

[matthewrose]

• OS mode. I get errors when I try to compile example in non-Os mode.

Progress Summary and ToDOs:

We achieved satisfactory performance of inventory timing (100-150ms) for 4 ICODE tags by performing scanning for only ICODE type V tags.

Now the problem is to read memory data of all 4 tags. There is not enough information how tag memory read APIs work after inventory is performed.

It will be helpful to understand how following API works. How they can be combined with tag inventory example ‘NfcrdlibEx1_BasicDiscoveryLoop’ to read memory (at least 4 bytes) from each ICODE type V tags present in field.

phalI15693_ReadSingleBlock

phpalSli15693_InventoryRead

phpalSli15693_InventoryPageRead

phpalSli15693_InventoryReadExtended

phpalSli15693_Inventory

phpalSli15693_SendEof

[marcinbaliniak]

Hi,

I want to join to this question. I'm using PN5180 over NXPLib and I can read UID using standard discovery loop but this is OK for few tags. But How can I use Inventory to read let say 100 tags on the antenna?

Now I'm calling with this parameters:

status = phpalSli15693_Inventory(pDiscLoop->pPalSli15693DataParams,

(PHPAL_SLI15693_FLAG_NBSLOTS | PHPAL_SLI15693_FLAG_DATA_RATE | PHPAL_SLI15693_FLAG_INVENTORY), //flags
0, //[In] Application Family Identifier.
NULL, //[In] UID mask, holding known UID bits.
0, //[In] Number of UID bits within pMask.
&bDsfid, //[Out] Data Storage Format Identifier.
uid);

And I get UID of "winner" tag, but to read other UID I should probably turn of this tag and repeat this procedure. But when try to call phpalSli15693_Select or phpalSli15693_StayQuiet I get error 0x0A25, but can't find in phpalSLI15693.h file errors description to decode this error.

Any hint how to perform inventory to read tags UID on the antenna will be useful.

[marcinbaliniak]

To be more precise after phhalHw_FieldReset() I first called phpalSli15693_Inventory() and I got UID.

Then I call phpalSli15693_StayQuiet() - it is fine also, and I'm assuming this command is received only by "winner" tag.

Then I call phpalSli15693_Inventory again and got 0x0201 error. 

Maybe I should send phpalSli15693_StayQuiet only for UID received by inventory but there is no phpalSli15693_StayQuiet with UID parameter... 

[Kan_Li]

Hi Matthew Rose,

Would you please try non-OS mode and check if there is any difference? To compile the project in non-OS mode, please kindly refer to PN7462 NON OS Build Errors for details.

Hope that helps,
Have a great day,
Kan

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[Kan_Li]

Hi Matthew Rose,

Would you please specify if you run the ‘NfcrdlibEx1_BasicDiscoveryLoop’ example with OS or without OS? Thanks for your patience!

Have a great day,
Kan