Is there any relation between connection parameters and occasionally disconnection

[Sansei]

I have a system, with cc2540 as central and n51822 as peripheral with s130. Sometimes while they are close to each other, the connection link gets lost. I disabled updating the connection parameters on the client(cc2540), and I set them just on peripheral. Is it acceptable or not? Where I can find best practices/settings on these parameters while I need to get fast feedback on getting out from the RSSI range and also need to do as much as fast on reconnecting;

Could you please clarify me with the impression of these parameters on my occasional disconnection problem?

[Sansei]

Thanks again. Actually, regardless of setting any value for CST (6S - 20S) when I set Connection Interval >= 600 ms I will get disconnection event in about 5 minutes after establishing the connection. Having a stable connection is very critical for us. At the second step, we also have to save the Battery as far as possible.

[Petter Myhre]

Then it is probably not the connection parameters that is the culprit. Do you get a BLE_GAP_EVT_DISCONNECTED event? Have you checked the disconnect reason? Have you checked that APP_ERROR_CHECK() isn't called with an error somewhere? And the device resets?

[Sansei]

Yes, as I said previously in question I get timeout error (0x8) exactly on BLE_GAP_EVT_DISCONNECTED event. No, it doesn't reset and there is no error somewhere really.

[Petter Myhre]

Ok. If you get BLE_HCI_CONNECTION_TIMEOUT on the nRF peripheral, it is either not able to receive packets from the central, or the central isn't sending out packets, and the it hits he supervision timeout. Have you tested the nRF peripheral with another central? For example nRF Connect on Android? Does it disconnect then? If not I would suspect that the issue is with the central device. This could be confirmed with doing a sniffer trace, to see what is actually happening on air.