Coded PHY (Long range) on S113

[Shahar]

Hi,

Looking at the differences between S132 and S140 SoftDevice, I see there's lack of support for Long Range (Coded PHY) on the S132 (and S112 for that matter), which is understandable as nRF52832 and nRF52810 do not have that capability.

But as S113 is designed to run on nRF52840, nRF52833, nRF52811 (and possibly nRF52820 based on Case ID: 252943 ) which all have Long Range capability, is there a reason Coded PHY was omitted from S113? 

Thanks

Shahar

[Marjeris Romero]

Hi,

Sorry for the late reply, we are in the mid of summer vacation here in Norway and have a reduce staff at the moment. S113 is an optimized version of the softdevice, with limited feature-set in order to reduce memory requirements. If you want to use the long range capability with nRF52811 or nRF52833 you should use the full version S140, but be aware of the size available for your application. S140 with MBR takes 156kB flash while the nRF52811 has 192kB of flash available.

Best regards,

Marjeris

[Shahar]

Hi,

Please correct me if I'm wrong here, but isn't Coded PHY is a hardware capability of the chip and less of a SoftDevice limitation (or implementation for that matter)?

I based my assumption on the following (all from latest SDK v17) minimum requirements:

S140: Flash 156KB (Using 39 4K flash blocks), RAM 5.6K, supporting nRF52840, nRF52833, nRF52820, nRF52811 and list goes on.

S132: Flash 152KB (Using 38 4K flash blocks), RAM 5.6K, supporting nRF52832, nRF52810, nRF52820

Besides the long list of devices certified for the S140 vs the S132 (which could explain the single 4K flash block difference), the only other major difference I can see is the coded PHY.

So, unless I'm mistaken, adding Coded PHY support to S113 ... will add in the worst case scenario 1 additional 4K flash block. And there's a high chance it might not, as Coded PHY is mostly handled in the hardware.
In terms on RAM, unless you enable it, it won't affect RAM requirements AFAIK. 

Can you please verify what is the actual SoftDevice footprint in enabling Coded PHY on S113?

[Marjeris Romero]

Hi again,

Coded PHY is a feature that puts requirements on both HW and SW. One factor that increases the flash usage is coded PHY itself, and the integration with the data length extensions.

One of the major reaons for not supporting Coded Phy on s113 is however the dependency on Advertising Extensions, which is a rather big feature. Hence, enabling Coded Phy on s113 would give a footprint similar to s140.

Coded PHY is still not a very widely used feature, partly because it has limited support on the phone side. Adding even just 4k to the S113 would affect all users of the s113 and only help a very small subset of them that needs this feature.

Best regards,

Marjeris