the connection inteval cannot updated

[Jim]

Nrf52832 based on sdk14.2 development as a slave, when linked with the iPhone, pairing and binding, and then get ancs service; and Android phone connection, direct communication is not paired, the first connection interval is updated after the connection 5s, the second time Updated after 30s, it is now found that when connecting to an Android phone, the connection interval can be updated normally, but when connecting with an iPhone, the connection interval cannot be updated. What is the reason?

[Mttrinh]

Hi,

What connection parameters are you using? Can you check if your parameters are within Apple's Guidelines?

[Jim]

I use the following paramenters：

#define MIN_CONN_INTERVAL               MSEC_TO_UNITS(25, UNIT_1_25_MS)            /**< Minimum acceptable connection interval (0.5 seconds). */

#define MAX_CONN_INTERVAL               MSEC_TO_UNITS(1000, UNIT_1_25_MS)           /**< Maximum acceptable connection interval (1 second). */

#define SLAVE_LATENCY                   0                                           /**< Slave latency. */

#define CONN_SUP_TIMEOUT                MSEC_TO_UNITS(6000, UNIT_10_MS)             /**< Connection supervisory time-out (4 seconds). */

#define FIRST_CONN_PARAMS_UPDATE_DELAY  APP_TIMER_TICKS(5000, APP_TIMER_PRESCALER)  /**< Time from initiating an event (connect or start of notification) to the first time sd_ble_gap_conn_param_update is called (5 seconds). */

#define NEXT_CONN_PARAMS_UPDATE_DELAY   APP_TIMER_TICKS(30000, APP_TIMER_PRESCALER) /**< Time between each call to sd_ble_gap_conn_param_update after the first (30 seconds). */

#define MAX_CONN_PARAMS_UPDATE_COUNT    3                                           /**< Number of attempts before giving up the connection parameter negotiation. */

[Mttrinh]

Hi,

How do you update the connection interval? Can you send me a sniffer trace? I seems like the default interval is within the wanted range so the SDK module won't send out a conn param update request.

[Jim]

Hi，

Attached for crawled air package data.conn_params_update_fail.pcapng

[Mttrinh]

It doesn't seem like you are sending an conn param update request from the peripheral. Like I said in my previous answer, seems like the default interval is within the wanted range so the SDK module won't send out a conn param update request.