NRF 5340DK CONFIG_BT_MAX_CONN cannot go above 5

Project based on NUS Central example.


Application is to connect to multiple peripherals concurrently running a custom service and subscribe to Notifications on a characteristic.

This i have working.

This is for an environmental measuring application, and ideally, the Central could support more than 40 concurrent connections.


No Pairing is required. connection is completed against a list of MAC Addresses

I have an issue where if i set CONFIG_BT_MAX_CONN to > 5 then there is a compiliation error

C:/ncs/v2.8.0/zephyr/include/zephyr/toolchain/gcc.h:87:36: error: static assertion failed: ""
   87 | #define BUILD_ASSERT(EXPR, MSG...) _Static_assert((EXPR), "" MSG)
      |                                    ^~~~~~~~~~~~~~
C:/ncs/v2.8.0/zephyr/subsys/bluetooth/common/dummy.c:75:1: note: in expansion of macro 'BUILD_ASSERT'
   75 | BUILD_ASSERT(CONFIG_BT_BUF_ACL_RX_COUNT > CONFIG_BT_MAX_CONN);

How can i Increase the number of connections?
I have tried to search for CONFIG_BT_BUF_ACL_RX_COUNT in the prj.conf

if I try to set CONFIG_BT_BUF_ACL_RX_COUNT it shows up as undefined.

using SDK vers 2.8.0

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