Does the nrf52832 has some delay when the shortcut of END_START is enabeled in continuous receiving?What is the meaning of rx chain delay?Does RX chain delay in 2Msps mode is 5us or 9.4us?

[jane_song]

Does the nrf52832 has some delay when the shortcut of  END_START is enabeled in continuous receiving?What is the meaning of rx chain delay?Does RX chain delay in 2Msps mode is 5us or 9.4us?

[Andreas]

Hi,

 

Unfortunately we do not have any numbers for this, I would expect it to be <1 µs. t_RXCHAIN is the time from a bit appears as energy on the ANT pin to the radio peripheral is aware of it, so that is not relevant.

 

Best regards,

Andreas

[jane_song]

Hi,
Thanks!Before I post the questions,I also browse some related Q&A.Some descriptions about rx chain delay seem differen as yours.Here are some links:
devzone.nordicsemi.com/.../what-is-rx-tx-chain-delay
devzone.nordicsemi.com/.../113978
Someone said: In other words you should be fine as long as there is a 10us delay between the end of the CRC of the first packet, and the start of the address of the second packet.
I'm so confused about the exact that.

[Andreas]

Hi,

 

No, this is the same but just a different explanation. For RX: if the first bit of the second packet appears on the antenna appears on the antenna immediately after the last bit of the CRC has been processed in the radio, it will take ~10µs (t_RXCHAIN) before the first bit makes it into the radio digital part.

 

Best regards,

Andreas

[jane_song]

Hi,

   Thanks.When choosing Nrf_2Mbit mode, does the exact  RX chain delay  is 5us or 9.4us?

[Andreas]

Hi,

 

nRF_2Mbps mode shares the typical 5µs RX chain delay with the BLE2_Mbps mode. nRF_1Mbps and BLE_1Mbps has typical 9.4 µs RX chain delay.

 

Best regards,

Andreas

[jane_song]

Hi,

  Thanks!As we all known,the tx or rx chaian delay is the delay between consecutive transmitting or receiving packets.TX chain delay is only 0.6us,however RX chain delay is 5us in 2Mbps.So when we transmit packests with 1us interframe spacing,the rx side can not dealing with the packets successfully.In other words,the least interframe spacing time must  be 5us to insure that consecutive packets can be receiving successfully.

[Andreas]

Hi,

 

Not quite. You can retransmit a packet to the nRF52 with 1µs interframe spacing, but the packet will not 'reach' the digital part of the radio receiver before after 5µs.

 

Best regards,

Andreas