How to reduce the response time of read requests

[Ryan Huang]

Hi,

I am working on the heart_rate_collector example code of nrf51-ble-driver_linux_0.5.0. I try to modify the example code let it can connect the Environmental Sensing Service (ESS profile) peripheral.

The ESS peripheral have temperature(Assigned Number: 0x2A6E) and humidity(Assigned Number: 0x2A6F) characteristic. Both of characteristic all support notify property.

When I connect the ESS peripheral and use the "sd_ble_gattc_read" to read its characteristic(such characteristic uuid: 0x2A29). Time between read request and read response is short.

But, when the notify function of temperature and humidity characteristic is be enabled, I also use "sd_ble_gattc_read" to read characteristic uuid: 0x2A29. Time between read request and read response is become very long.

I capture this sniffer packet sniffer.pcapng

And then, I use my android smart phone and install "nRF Connect for Mobile" APP to connect the ESS peripheral. Time between read request and read response is always short. (even the notify function of temperature and humidity characteristic is be enabled)

Does anyone have any way to reduce the response time of read requests?

[Ryan Huang]

Hi Hung Bui,

I start a timer and then setting 1s timeout to sample data and and send data with hvx.

Please see code snippet

Thanks

Ryan