ble_app_uart is too slow for IOS,how to fix it?

[qoboty]

I use ble_app_uart of IOS,but the Tx speed is about 200B/s(send 20B for 100ms), why ? how to speed up to 20KB/s ? Thank you!

[qoboty]

Thanks for your answer, Are you sure about "1 packet is sent every connection interval" of Nordic UART Service (NUS) ?? Can you figure me out ? Thank you!

[FormerMember]

It should not be any problem to send multiple packets per connection interval with the ble_app_uart example in the SDK.

[FormerMember]

The connection interval range is defined in the Bluetooth Core Specification 4.2, vol 3, part C, chapter 12.3: 7.5 ms to 4s.

[Hieu]

@qoboty: I was actually wrong about that. I was looking at the ble_nus_string_send() method and see that it only call sd_ble_gatts_hvx() once, and thought that that means this service only send one notification at a time. It never occurs to me that I could bypass that helper function and purposefully call sd_ble_gatts_hvx() multiple times.

However, while doing that, I have encountered something pretty strange. Even though I have 13 notification calls every external event, only 7 notifications happened. I am going to open a question on that.

@kristin: Sorry about the mistake. I have updated the question to reflect it now.