nrf52832 Can't receive the message from phone on time (phone send every 100ms ) ？

[zk017]

SDK 14.0 +nrf52832:

           We use phone to send command to our toy(nrf52832) every 100ms to  control a motor accurately，mostly toy received command  is long than 100ms(more than 200ms, a little is less than 100ms), the especially on Android app.  I wander how to impove the accurate when receive command from android app， is there any parameter adjust to match the accurate need?

[run_ar]

Hi,

Do you know what connection interval you get when connecting to Android? Do you send a connection parameter update request to the peer? If so what settings do you use? OR are you saying the connection interval is always 100ms, but there is additional latency in android upper layers?

[zk017]

run_ar, thanks for your answer. connection param at toy(nrf52832) is set as following. I use sniffer tools and found additional latency is always in app(android phone) , not accurate 100ms. so I want to know is any parameter in my toy can be update to affect the android phone: to let phone can send command on a accurate 100ms every time

#define MIN_CONN_INTERVAL               MSEC_TO_UNITS(10, UNIT_1_25_MS)             /**< Minimum acceptable connection interval (20 ms), Connection interval uses 1.25 ms units. */
#define MAX_CONN_INTERVAL               MSEC_TO_UNITS(40, UNIT_1_25_MS)             /**< Maximum acceptable connection interval (40 ms), Connection interval uses 1.25 ms units. */
         
#define SLAVE_LATENCY                   0

[run_ar]

Did you check what connection interval you are actually getting from the phone?

Unfortunately I do not think there is much else that can be done to improve the latency.