CC2642R: Packet resend speed after connection established

Hi,

I cannot tell how many connection intervals should occur before the packet is sent. This will depend on the number of packets required to exchange the GATT table and other connection information. On the top of that some connection packets might be missed an lead to a slightly higher number of connection events elapsed.

I recommend to use a Bluetooth LE Logger in order to have a clearer picture of the number of connection interval really required to send the packet.

In addition to that, instead of using a timer, I would rather trigger the transfer at the completion of the GATT table discovery (called service discovery in multi_role example). That way you would get a timing that is neither too short nor too long. If you are interested by this solution, in multi_role example, please review the function multi_role_processGATTDiscEvent() and find the line with the comment "// Now we can use GATT Read/Write".

I hope this will help,

Best regards,

Hi Clément,

You mean that the intervals may be changed after GATT table exchanged ? Even if I set both master/slave intervals to 100~150ms in multi_role.sysconfig? As i know , the interval is depend on master.

I will consider the get the timing from GATT table discovery.

BRs,
Zell Wu

Hi,

No I meant the GATT table exchange may take more or less time due to the size of the GATT table itself and the amount of packet losses.

Regards,

Hi Clément,

Both device was connected and the Master got the CHAR1 handle. I think it should not exchange the GATT table again. (Am I wrong?)
After I use multi_role_doSelectConn to work with the slave, I use "multi_role_doGattWrite" to send the packet for each 500ms.

Here is flow:
Discovery--> Connect --> Communicate with --> start timer to send packet

BRs,
Zell Wu

Hi,

You are right the GATT table is discovered only at connection.

Your work flow is correct.

Next step is to verify with a BLE logger to see how the packets are sent.

Regards,

Hi,

Which BLE logger you described? And how to open it?

BRs,

Hi,

You can use a dedicated tool such the ones provided by Ellisys. You could also use our Packets sniffer. For additional guidance with this tools, please open a new thread.

Regards,