Muliple 247 packet in each connection interval

[chetan98]

Hello Nxp Team,

I need confirmation that central and peripheral device will communication during connection event, which is define from connection interval?

I want to multiple packets of 247 byte packet each in less than time of connection interval if my connection interval is 22 ms and my bluetooth data sending timer send data at 5ms so 4 sample will be in the queue and every 22ms data will be sent from peripheral to central.

Can Nxp confirm the understanding?

with regards

Chetan

[luis_maravilla]

Hello Chetan,

During a connection event, the Central and Peripheral alternate sending and receiving packets, The connection event is considered open while both devices continue to send packets, creating a communication.

Connection Interval shall be a multiple of 1.25 ms in the range 7.5 ms to 4.0 s

For more information about this please refer to Bluetooth Core Specification, Vol 6, Part B, Section 4.5.1

While is it recommended to design small attribute value sizes, GATT layers as Wireless UART can only send 23 bytes of data in a radio packet setting the ATT packet default length to 23, The ATT packet length is set to maintain a logical mapping between radio packets and ATT packets.

I would strongly recommend checking the series[1-4] of community post  Bluetooth Low Energy - Working with long attributes on a GATT Server - Part 1: ATT_MTU - NXP Communi... if you need to send more bytes of data, as explains how to write long attributes involves writing queues, and modifying the ATT_MTU for both GATT client and server to support larger MTU with MTU exchange.

Best Regards

Luis