Recent Posts

1

Bluetooth Framework / Re: Bluetooth framework with Unity

« Last post by Mike Petrichenko on November 03, 2022, 12:24:04 PM »

New demos available by this link: https://github.com/btframework/Wireless-Communication-Library-Unity-Samples
This demos use native .NET libraries and does not require C++ wrappers.

2

Bluetooth Framework / Re: Unpredictable GATT Client Connects

« Last post by briandunham on September 15, 2022, 06:38:51 PM »

Ah okay. A simple reconnect makes sense here and it's easy enough to implement clean reconnects. Thanks!

3

Bluetooth Framework / Re: GATT Client - How Can I Improve Transmission Rate?

« Last post by Mike Petrichenko on September 15, 2022, 06:14:53 PM »

I should mention here that I was able to drastically improve my throughput by setting the connection interval on the server side (not Windows 10). And when the connection is established, the client and server negotiate the connection params which causes Windows 10 to adjust the connection interval properly.

That is absolutely correct way and I 100% agree with this solution. If you can adjust any params on your HW side (not on Windows one) it is always right way. Because MS does not allow to control too much things in BLE communication.

4

Bluetooth Framework / Re: Unpredictable GATT Client Connects

« Last post by Mike Petrichenko on September 15, 2022, 06:13:08 PM »

Unfortunately no. All you can do is change connection interval on Windows 11 or with BLED112 dongle.

More universal solution is simple try to reconnect: once you get this error during connection simple try to connect again.

5

Bluetooth Framework / Re: GATT Client - How Can I Improve Transmission Rate?

« Last post by briandunham on September 15, 2022, 06:11:29 PM »

I should mention here that I was able to drastically improve my throughput by setting the connection interval on the server side (not Windows 10). And when the connection is established, the client and server negotiate the connection params which causes Windows 10 to adjust the connection interval properly.

6

Bluetooth Framework / Re: Unpredictable GATT Client Connects

« Last post by briandunham on September 15, 2022, 06:06:00 PM »

I am always doing a discover before connecting and there are no other connections. So I'm wondering if it might be something else.
The server is running on an RTOS system that has other processes running. And those other processes might block the bluetooth process depending on priority. Is there some kind of timeout that the client has if the server doesn't respond quick enough? Could that timeout be extended?

7

Bluetooth Framework / Re: Unpredictable GATT Client Connects

« Last post by Mike Petrichenko on September 15, 2022, 09:03:25 AM »

Hello,

This error usually appears if the server has random MAC and the MAC was changed while client trys to connect with previous MAC. Rediscovering should help.
Also this error may appear if the server accepts only single connection and the previous one was not closed yet (on server side). Closing connection usually takes about 2 * connect_interval.

8

Bluetooth Framework / Unpredictable GATT Client Connects

« Last post by briandunham on September 15, 2022, 01:52:49 AM »

I am sometimes getting a WCL_E_BLUETOOTH_LE_CONNECTION_ESTABLISHING_FAILED (0X00051081) error when connecting to a GATT server. The error description says "LL initiated a connection but the connection has failed to be established. Controller did not receive any packets from remote end." Is there any way to make this more reliable from the client side? Like a longer wait before it throws an error?

9

Bluetooth Framework / Re: GATT Client - How Can I Improve Transmission Rate?

« Last post by Mike Petrichenko on August 10, 2022, 08:52:34 AM »

By the way, latest version allows to get max PDU size (and has event to notify when max PDU size changed). So you can split your data to the max PDU size (-3 bytes) to send it more affective.

10

Bluetooth Framework / Re: GATT Client - How Can I Improve Transmission Rate?

« Last post by Mike Petrichenko on August 10, 2022, 06:28:17 AM »

Unfortunatellyu no. BLE (and GATT) was designed for power saving, not for bulk data transferring. For big data you should use classic Bluetooth. Not GATT. Of course modern BT 5 allows to transfer audio and video but it does not use GATT for that.