Any way to increase TX buffers on S110 (nrf51822) ?

[Ben Gray]

I've read that the number of tx buffers on the S110 is fixed at 6, however I've also read that this may be configurable on future versions of the softdevice (devzone.nordicsemi.com/.../

I can't find any API to set the tx buffers so I assume this never happened, can anyone confirm? I'm hoping there is some hidden option or magic version of the S110 that we could use with this limit increased. Any help would be greatly appreciated.

Unfortunately having only 6 TX buffers is a bit of a show stopper for my project. Our board runs in a noisy environment and often misses connection intervals, with only 6 buffers we can't recover in the next connection interval and have to drop packets.

(FWIW - using a TI chip we were able to push though more than 6 packets per connection interval and that gave us better immunity to noise and we therefore could maintain better bandwidth ...)

[Sigurd]

Hi,

You are unfortunately limited to 6 packets per connection interval with the nRF51-series SoftDevices.

On the newest nRF52-series SoftDevices you don’t have this limitation, and the SoftDevice is able to continue sending packets for the whole connection interval. With the nRF52 series you get a support for significantly higher throughput. With ATT MTU size set to 247 and LL payload size set to 251 you can achieve up to 771.1 kbps throughput in 1Mbps mode, and up to 1376.2 kbps in 2Mbps mode. See this link for more information.

[Ben Gray]

Thanks for the (very) quick reply. Although it's a bit disappointing ... guess I'll just have to push for a nRF52 chip :-).