connect inteval time

RE: connect inteval time

ovrebekk — Tue, 08 Jan 2019 12:39:46 GMT

As mentioned before, all you can do is set the MIN_CONN_INTERVAL and MAX_CONN_INTERVAL defines, and hope that the central will give you the connection interval that you are asking for.

Set both of these to MSEC_TO_UNITS(250, UNIT_1_25_MS) to request this particular connection interval.

You can also try to increase the MAX_CONN_PARAMS_UPDATE_COUNT parameter, which will increase the amount of times that the peripheral asks for updated connection parameters.

Best regards
Torbjørn

RE: connect inteval time

Carey — Tue, 08 Jan 2019 01:26:18 GMT

i use the BLE uart example to test. I want to change the connected interval to 250ms, How to set is right?

RE: connect inteval time

ovrebekk — Mon, 07 Jan 2019 10:13:31 GMT

What kind of BLE device are you connecting to?

It is up to the central whether or not to heed the values stored in the PPCP. In the end the central can set the connection parameters to whatever it likes.

Best regards
Torbjørn

RE: connect inteval time

Carey — Sun, 23 Dec 2018 14:09:17 GMT

static void on_ble_evt(ble_evt_t * p_ble_evt)
{
uint32_t err_code;

switch (p_ble_evt->header.evt_id)
{
case BLE_GAP_EVT_CONNECTED:

m_conn_handle = p_ble_evt->evt.gap_evt.conn_handle;

min_interval=p_ble_evt->evt.gap_evt.params.connected.conn_params.min_conn_interval;
max_interval=p_ble_evt->evt.gap_evt.params.connected.conn_params.max_conn_interval;

HI, I have read the connected interval data like this, both of the min_interval and max_interval is 39 (0x27), despite i set the MIN_CONN_INTERVAL is 350ms, MAX_CONN_INTERVAL is 450ms ,

RE: connect inteval time

ovrebekk — Tue, 04 Dec 2018 17:42:16 GMT

You can check the connection parameters you are given in the connected or conn params update events, and print them to the log:

case BLE_GAP_EVT_CONNECTED:
.
.
NRF_LOG_INFO("Con params: %i, %i", p_ble_evt->evt.gap_evt.params.connected.conn_params.min_conn_interval, p_ble_evt->evt.gap_evt.params.connected.conn_params.max_conn_interval);
break;

case BLE_GAP_EVT_CONN_PARAM_UPDATE:
NRF_LOG_INFO("Con params: %i, %i", p_ble_evt->evt.gap_evt.params.conn_param_update.conn_params.min_conn_interval, p_ble_evt->evt.gap_evt.params.conn_param_update.conn_params.max_conn_interval);
break;

Just multiply the reported number by 1.25 to get the interval in milliseconds.

Then you should at least know if the values you see in the log are related to the connection interval.

Best regards
Torbjørn

RE: connect inteval time

natersoz — Mon, 03 Dec 2018 15:06:48 GMT

I misread your post - sorry. Although the central can ignore your connection parameter request I don't think this is happening in your case. It usually happens when the connection interval request is too small. In your case, I don't know why you're getting 50 msec burst in power. Are you sure it is related to radio on time?

RE: connect inteval time

Carey — Mon, 03 Dec 2018 01:31:13 GMT

you mean that in my broad the real connect time is 50ms? despite I set the MIN_CONN_INTERVAL and MAX_CONN_INTERVAL is 250ms to 350ms, the central can reject that parameter and set it freely?

RE: connect inteval time

natersoz — Sat, 01 Dec 2018 19:47:29 GMT

The connection parameters when set by a peripheral merely set the PPCP Preferred Peripheral Connection Parameters characteristic (I am assuming that you are discussing the performance observed on the peripheral side of the UART).

The host, i.e. central, can read the PPCP characteristic and accept or reject the parameters. It is completely optional. If rejected, the peripheral cannot stray outside the negotiated connection parameters.