Always connected peripheral

[Oleh]

What should the connection or other settings be to have a peripheral always connected? It is a bit contradictory for low energy device, however for a lost&found (link-loss and immediate alert services) this is required.

We experience in testing with different connection intervals and latency the tag is disconnected from the phone after some time.

the power_off is not used, so I expected to be always on, instead it enters the advertisement after disconnect.

Could you please suggest or hint on what we are doing wrong? Or share your experience with similar projects.

thank you, cheers Oleh

[Oleh]

Short update.

Did some more testing and changed several times connection parameters.

having these:

#define MIN_CONN_INTERVAL MSEC_TO_UNITS( 20, UNIT_1_25_MS) // prev val: 200

#define MAX_CONN_INTERVAL MSEC_TO_UNITS(1000, UNIT_1_25_MS) // prev val: 2000, 1500

#define SLAVE_LATENCY 0 // always 0

#define CONN_SUP_TIMEOUT MSEC_TO_UNITS(4000, UNIT_10_MS) // prev val: 6000, 5000

the disconnection is not immediate.

scanning with wireshark there are frequent LL_CHANNEL_MAP_REG packages, then some LL_PING_REQ with the LL_UNKNOWN_RSP, and until new connection values were set frequent BLE_GAP_EVT_CONN_PARAM_UPDATE events in the log. with new min_conn_intervall these disappeared.

...

[Oleh]

a short statistic of last 3 hours of testing the disconnect-issue, here are the values I've got with my comment:

• 0x2a > initial test
• 0x3e > probably due to uart logging lots of data (detailed)
• 0x16 > dunno why...
• 0x08 > as soon as I changed some connection params.

[Petter Myhre]

Sorry for the late response, did you see comment from Runar in the other question?

[Oleh]

yes, thank you! will follow the other thread.