Max connections count in SDK 12.2

RE: Max connections count in SDK 12.2

tesc — Fri, 26 Jun 2020 09:58:34 GMT

Hi,

S132 v3 supports up to eight connections, according to the SoftDevice Specification v3.1. This means eight connections is the maximum for nRF5 SDK v12 with S132 v3. If you are working on a new project and use an nRF52 series device, I strongly recommend using the latest version of nRF5 SDK, which is currently version 17.0.0.

What SDK is used with what SoftDevice (with what SoftDevice Specification), and for what device / SoC revision, can be read from the SDKs and SoftDevices compatibility matrix for each device.

Regards,
Terje

RE: Max connections count in SDK 12.2

SultanArabi — Thu, 25 Jun 2020 16:19:02 GMT

Thanks a lot, it makes sense.

RE: Max connections count in SDK 12.2

SultanArabi — Thu, 25 Jun 2020 16:18:25 GMT

Thank you for your co-operation.

Yes, I noticed that, but as you know, the comment isn't evidence and thought that maybe a configuration or patch that fixes this issue.

RE: Max connections count in SDK 12.2

awneil — Thu, 25 Jun 2020 16:11:04 GMT

[quote userid="91487" url="~/f/nordic-q-a/63043/max-connections-count-in-sdk-12-2"]I try to increase the CENTRAL_LINK_COUNT from 8 to 9[/quote]

The code you posted suggests that the maximum is only 8:

[quote userid="91487" url="~/f/nordic-q-a/63043/max-connections-count-in-sdk-12-2/257001"]// Use the max config: 8 central, 0 periph, 10 VS UUID[/quote]

You need to check the specific documentation for the version you are using

RE: Max connections count in SDK 12.2

Turbo J — Thu, 25 Jun 2020 16:02:29 GMT

The support for 20 connections in softdevice S132 came with version 5.0.0 according to the release notes - that is probably too new for SDK12.

Which version do you use?

RE: Max connections count in SDK 12.2

SultanArabi — Thu, 25 Jun 2020 15:55:51 GMT

In SDK 12.2 the CENTRAL_LINK_COUNT and PERIPHERAL_LINK_COUNT are defined in the main.c and are passed to the SD like this:

ble_enable_params_t ble_enable_params;
    err_code = softdevice_enable_get_default_config(CENTRAL_LINK_COUNT,
                                                    PERIPHERAL_LINK_COUNT,
                                                    &ble_enable_params);
    APP_ERROR_CHECK(err_code);

    // Use the max config: 8 central, 0 periph, 10 VS UUID
    ble_enable_params.common_enable_params.vs_uuid_count = 10;

    // Check the ram settings against the used number of links
    CHECK_RAM_START_ADDR(CENTRAL_LINK_COUNT,PERIPHERAL_LINK_COUNT);

    // Enable BLE stack.
#if (NRF_SD_BLE_API_VERSION == 3)
    ble_enable_params.gatt_enable_params.att_mtu = NRF_BLE_MAX_MTU_SIZE;
#endif
    err_code = softdevice_enable(&ble_enable_params);
    APP_ERROR_CHECK(err_code);

and I got this error:

RE: Max connections count in SDK 12.2

awneil — Thu, 25 Jun 2020 15:47:55 GMT

[quote userid="91487" url="~/f/nordic-q-a/63043/max-connections-count-in-sdk-12-2"]I got this error[/quote]

Where, exactly, did you get that error ?

I don't know about SDK 12.2, but by v15 there were separate counts for Central and Peripheral links - so are you sure you updated the right one?

There might also be another separate "total links" count ...