ANT Forum

Hi,

I am using Shared channel configuration. With one master and four slave connected.

i am using NRF51422 module with SDK_5.2.0 and soft-device S310.

I am sending burst message of 72 bytes.

sometimes it happens like Slave received the burst data but master side i got EVENT_TRANSFER_FAILED(master fails to send data) and vice verse.

Above behavior is normal or not?

Thanks
     

No the behaviour is not normal. Are you sending the Burst Transfers to a specific shared address or to shared address 0?

Also, you are using the S310 softdevice, are you also running BLE concurrently while this shared channel is in operation?

     

I am sending burst to specific shared address.

In Master i am not using BLE concurrently, but in slave i am using it.
The error rate i observed in Master and slave is nearly same.

Also note that i am sending the entire 72 byte at once.


     

Hi,

I think forum is supposed to get answer not to hang the questions in air.
Hope i will get some response for this thread.

Thanks      

Hi,

It would be helpful if you could provide some details.

What exact failure rates are you seeing at both the master side and the slave side? What failure rates are you aiming for?

What is your RF environment like? Have you tried different RF frequencies for your application? (try to avoid the frequencies used by WiFi: http://en.wikipedia.org/wiki/List_of_WLAN_channels).

Can you also test what kind of failure rates are observed with BLE disabled? Both ANT and BLE share the same radio on the nRF51422, and resource intensive tasks like burst messaging can result in a decrease in performance.      

hi,

I am using NRF51422 module. with "s310_nrf51422_1.0.0_softdevice" and shared channel configuration with single master and multiple slave(max 4 slave).

Master side:
1. The burst sending failure rate for is 20% without retrial.
2. the burst sending failure rate is 9% with single Application level retrial

Slave side
1. The burst sending failure rate is 4% without retrial.
2. the burst sending failure rate is 0.8% with single Application level retrial

i am aiming for failure rate less less than 4%.

I have tried 2410MHz, 2466MHz,and 2470MHz,

I need to test with BLE disabled in both master and slave.

Note:
In Master device firmware, Only single ANT channel is active.
For slave device both ANT and BLE are active.
I am sending 72 bytes burst in a single shot.
Chanel period used is 4Hz and burst sending interval is 15Second.      

Hi,

Have you had any progress in reducing the failure rates for your use case?

Did you get a chance to test with BLE disabled on both master and slave? Any notable changes in failure rate?