Confusion about BLE connection interval and how often the Peripheral will send data to the Central

RE: Confusion about BLE connection interval and how often the Peripheral will send data to the Central

Tai — Fri, 01 Jul 2022 15:21:34 GMT

It makes sense anh. I'll definitely watch the video you suggested. Thank you for your answer!

RE: Confusion about BLE connection interval and how often the Peripheral will send data to the Central

Tai — Fri, 01 Jul 2022 15:20:36 GMT

Thanks Zara for this!

RE: Confusion about BLE connection interval and how often the Peripheral will send data to the Central

Hung Bui — Fri, 01 Jul 2022 09:17:31 GMT

Hi Tai,

You can watch a BLE tutorial here.

Be noted that in each connection event (or in other words "in each connection interval") the central will send a packet to the perpiheral. It's not the central asking for data from the peripheral. It can be an empty packet from the central and if the peripheral has any data it can choose to send data otherwise it can send an empty packet back.

It's a way of keeping the connection alive. The slave can choose not to reply (slave latency) but it should reply (either with data or with empty packet) before the connection is terminated because of the inactivity timeout.

The handling of sending empty data or skip the responding (slave latency) is handled by the BLE stack so the application doesn't need to handle this.

In your case you send data every 10 seconds, so most of the time it will just reply to the central with empty packet and every 10seconds sending a data packet.

RE: Confusion about BLE connection interval and how often the Peripheral will send data to the Central

Zara Wu — Fri, 01 Jul 2022 09:05:37 GMT

Hello,

Using timer_callback, the 10 seconds here can not be determined as how often the Peripheral will send the data to the Central.

If no data is sent from the peripheral to the central, the BLE protocol also stipulates that heartbeat packets will be sent according to the connection interval settings.

Hope it helps.

BR./Zara Wu (RF-star technology)