S130 connection offen break

[Songplus]

Hi,I use S130 V1.0 working as a master,and connect a device.My device adverting interval is 800ms， and gap_conn_params.min_conn_interval = MIN_CONN_INTERVAL;//MIN_CONN_INTERVAL=500ms ,gap_conn_params.max_conn_interval = MAX_CONN_INTERVAL;//MAX_CONN_INTERVAL=1000ms.The master scan param is : scan interval=1000ms ,scan window=500ms,and the master connection param is:MIN_CONNECTION_INTERVAL=25ms,MAX_CONNECTION_INTERVAL=937ms.When I use the following function err_code = sd_ble_gap_connect(m_sys_data_store.obd_addr.addr,m_scan_param,m_connection_param);,err_code = NRF_ERROR_INVALID_PARAM.If change the master connection param to MIN_CONNECTION_INTERVAL=7.5ms,MAX_CONNECTION_INTERVAL=30ms,the master can connect to the device ,but the connection offen breaks,the device notification data lost .How to solute the problem?

[Songplus]

I think the MCU NRF51822 frequency is too low to immediately implement the SD IRQ after the UART IRQ handler.

[FormerMember]

To find you why the connection breaks, you will need to do some debugging: What is the reason for the disconnect? Does any of the devices actively disconnect the link for instance?

[Songplus]

After connecting,the master keep connecting for receiving the device notify. Device send notify every second,but the master go to disconnect after missing receive some device notify.

[FormerMember]

How does the disconnect happen, is it connection supervision timeout, a hardfault, app_error_handler triggering a reset, or is sd_ble_gap_diconnect() explicitly being called? I would recommend you to check both the central and the peripheral side of the link.

[Songplus]

It is master sd_ble_gap_diconnect() happen.Device connect to the NRF Connect APP , never happen connect break for a long time connection.I sure that device has not error ,because I have use the device frame in my production for 2 years ,and never happen connection break for app using.