About scan timeout

[June6]

Hi,

I am using SDK 17.1.0 as a host scanner. When I changed the timeout to 0, there was a problem with the connection slave (NRF_ERROR_INVALID_PARAM). I'm pretty sure the problem is not caused by other conditions. Because other parameters remain the default. So when I want the scan to never time out, can I only restart the scan after the timeout?

[June6]

Oh! I see. The scan timeout parameter is NRF_ BLE_ SCAN_ SCAN_ DURATION. Not NRF_BLE_SCAN_SUPERVISION_TIMEOUT. 

But why is it wrong to change this parameter from 4000 to 0?

[Einarh]

Hello!

According to the documentation, NRF_BLE_SCAN_SCAN_DURATION can be set to 0x0000 to continue indefinitely:

https://infocenter.nordicsemi.com/index.jsp?topic=%2Fsdk_nrf5_v17.1.0%2Fgroup__nrf__ble__scan__config.html&cp=8_1_6_2_15_0_9&anchor=gacdb9b51bb850e2dcb8b07baa78d45402

But have you made sure all your scanning parameters are compatible with each other?

You might have to change some of the other default parameters before you can remove the scan timeout.

Best regards,

Einar

[June6]

Thank you for your prompt reply.

I treat NRF_BLE_SCAN_SUPERVISION_TIMEOUT as a timeout parameter.

I set this parameter to 0, and then a connection error occurred. The error code is NRF_ERROR_INVALID_PARAM.

I don't understand the meaning of this parameter and why it can't be set to 0.

The premise is that other scanning parameters remain the default (the routine used is uart_c)

[Einarh]

It's possible that NRF_BLE_SCAN_SUPERVISION_TIMEOUT is not allowed to be 0, and this could be causing your error.

Do you know exactly what function in your code is returning the error code?

-Einar

[June6]

sd_ble_gap_connect();  

return error code NRF_ERROR_INVALID_PARAM