Connection stability with S130

[Marius Heil]

Hello,

has anyone done some good testing on the connection quality between multiple nRF51 chipsets running on the S130 SoftDevice? (Using all four connections, 3 as Central, 1 as Peripheral) Given an environment with very low interferance and a timeout of 6 seconds with a connection interval of 100ms, can the SoftDevice stay in connection for multiple months? I am currently experiencing connection losses at a rather high frequency (about 2-3 per day) and I am wondering wether this is a bug that I introduced somewhere in my code. At times, I receive the BLE_GATTC_EVT_TIMEOUT event which basically forces me to close the connection. But I am wondering why this happens, because both sides process the BLE events quickly.

I guess that Nordic has done quite a bit of testing on connection stability, would you share these results?

Thanks, Marius

Edit: I am initializing the SoftDevice with NRF_CLOCK_LFCLKSRC_XTAL_20_PPM, maybe that is part of the issue, I am currently investigating this.

[vich]

Hi Marius,

We do stress test the multiple concurrent connections. Please provide details of your firmware (SD versions, GAP and GATT procedures exercised, etc.), to better understand your observations.

I would like to bring your attention towards the fact that peripheral links drift in time and overlap over multiple Central links in time on a chip, but as you have 100ms and 6s timeout, each link should sync within few retransmissions; hence disconnections should not be observed.

continued...