Issue with connection Interval

[adityaj]

I am using nrf52832. I am setting MIN and MAX Connection Interval both to 7.5 ms as android support 7.5 ms connection interval. We are getting 2-3 packet in one connection interval in nrf APP. I am getting around 8 ms delay between each connection interval with one android phone but when we are testing the same code with other android phone, we are getting around 50 ms delay between connection interval packets. I also tried to change the MIN and MAX Connection Interval to 7.5 ms and 30 ms respectively, but getting same result.

I have two question :

1. How we can reduce this delay between connection interval?
2. Right now, I am sending 20 bytes packet data continuously as notification. We are getting 200 packets in 1 sec (throughput around 4kbps) with MIN AND MAX Connection Interval of 7.5 ms. How we can increase this throughput?

Below My code main.c

[shibshab]

To achieve max throughput, take a look at the throughput example for SoftDevice configurations (DLE, ATT MTU etc.)

[ketil]

Hi,

1. We have seen that Android phones can behave differently in regards to BLE. Which phones are you performing the tests with?
2. The nRF52832 supports the high throughput feature of Bluetooth 5. This would increase your throughput but only a few Android phones support Bluetooth 5 at this point in time (Pixel 2, Pixel 2 XL, newest high-end Samsung). If these phones are not an option then you should follow the suggestion from @shibshab.

Ketil