Following a ReqRN request (to obtain the handle) 4 bytes are received. Can Anyone tell me what those 4 bytes are? Or where in those 4 bytes the handle in located? TIA

[Bart Herse]

Hello Andrew,

the first two bytes are the Handle/RN16 and the remaining bytes are CRC-16. Please check the Gen2V2 spec. or the ISO18000-63 standard.

Cheers,

B

[CShac]

Many thanks. I assumed as much however it seems sometimes the CRC is not valid, but that ok I can work with that.

[CShac]

Hi Bart,

Further to my question. I seem unable to ever retrieve an RN and matching CRC when using the REQ_Rn Direct command. The Rx length register is set up to receive 4 bytes and an EPC code has been successfully read prior to the Direct Command 9Fh being issued

[Bart Herse · Accepted solution]

Hello Chris,

did you send the Req_RN command while the tag was in the Acknowledged state? Note: if the Req_RN is not sent within the T2 timing constraint the tag will leave the Acknowledged state and return to the Arbitrate state. Please check the required timing constraints and the tag state diagram in the Gen2V2 spec.

Cheers,

B

[CShac]

Hi Bart,

My apologies, yes I believe my timing was slightly out. I have now solved this issue.

Thanks for coming back to this.

Chris