Maximum link number of NCS project

[helen]

HI Nordic,

As far as I know, in nRF5SDK, the maximum link number of BLE is 20.

I search for the devzone, someone said the number for NCS is 64. 

So, I want to know:

1、whether the maximum link num of NCS(zephyr) is 64?

2、Where to set the parameter in NCS project?(I know in nRF5SDK in the sdk_config.h and so on)

[haakonsh]

Hey Xuntong,

1. Yes, the maximum number of connections is 64, see https://docs.zephyrproject.org/latest/reference/kconfig/CONFIG_BT_MAX_CONN.html.
   
   
2. You need to set CONFIG_BT_MAX_CONN=x, where x is your desired number of connected devices, in your prj.conf file.

Note that there is no guarantee that the stack can service 64 connections at once, it depends on entirely on your connection requirements.

BR,
Håkon Holdhus

[helen]

Hi Håkon Holdhus，

some more questions.

1、The zephyr controller support up to 64 devices, what about the softdevice controller, does it also support 64 devices,or just 20 devices like nRF5 SDK?have it been tested?

2、As for 52 series, when the nRF52xxx serve as just controller(host is placed on other IC) , or the controller and host both place in the IC, does the maximum number make a difference?

[haakonsh]

1. we theoretically support 30 devices, test with 20 devices, but in Softdevice (i.e. not NCS) regression. The link layer is the same so it should work the same in NCS as Softdevice.
   
   
2. the maximum number shouldn't make a difference, but the controller should be programmed with the same (or greater) number of devices that the host wants to make use of.