Starterware/CC2640R2F: CC2640R2F Changing MTU size

Siva Krishna Kattinti

Part Number: CC2640R2F
Other Parts Discussed in Thread: CC2540, CC2650

Tool/software: Starterware

Hi *,

I want to change the number of bytes write/ read in single characteristic at time. I want to read 48 bytes in 1 characteristic at time. So I have gone through the Software Development Guide and made changes in BleUserConfig.h by changing the MTU size from 27 to 48. Compiled and flashed. But when I am trying to read that particular characteristic in Android smart phone by using nRF Control App, that particular characteristic is keep on loading and after that getting an error TIMEOUT.

Could anyone please describe the procedure did I need to changed other than MTU_SIZE, Is it possible that I can check with by using this CC2540 dongle with BLE Device Monitor.

Thanks for your response in advance.

Thanks,

Siva.

over 8 years ago

0 Christin Lee over 8 years ago

TI__Guru 56345 points

One top of that, you also need to make sure that MTU_Size is exchange over the air. The client has to request Exchange MTU Request so that the server can respond.

0 Siva Krishna Kattinti over 8 years ago in reply to Christin Lee

Expert 1090 points

Yes I agree with your point. Is there any TI provided Ble Apps are available to check the MTU size which is more than 23 bytes.?

Thanks,
Siva.

0 Christin Lee over 8 years ago in reply to Siva Krishna Kattinti

TI__Guru 56345 points

Hi,

I am not aware of any TI apps does that. But you can try to use simple_central project to just verify that it works.

0 Siva Krishna Kattinti over 8 years ago in reply to Christin Lee

Expert 1090 points

Is there any ble Central dongle from TI is available where MTU size is more than 23 bytes.

Thanks,
Siva.

0 Christin Lee over 8 years ago in reply to Siva Krishna Kattinti

TI__Guru 56345 points

Hi,

There is no dongle available for what you want since we only have CC2540 dongle which can't support BLE version 4.2.

You can get a CC2650/CC2640R2 launchpad to do the test.

0 Siva Krishna Kattinti over 8 years ago in reply to Christin Lee

Expert 1090 points

Thanks so much for your reply.

For CC2650 is there any Python Interpreter API's are available?

Thanks,
Siva.

0 Christin Lee over 8 years ago in reply to Siva Krishna Kattinti

TI__Guru 56345 points

Hi,

I am not following what you are asking. What are you trying to do with CC2650? Can you elaborate that a bit more so we can assist you better.

0 Siva Krishna Kattinti over 8 years ago in reply to Christin Lee

Expert 1090 points

Hi,

If I say in simple words, I will flash Host Application into CC2650 with the MTU size of as you mentioned 240 Bytes. Next I don't want to use BLE device monitor, instead I want to run python script which will perform particular peripheral Service, Characteristic Data I am able to read. This is I want to know whether there is any python script is already exist?

Thanks,
Siva.

0 Christin Lee over 8 years ago in reply to Siva Krishna Kattinti

TI__Guru 56345 points

Hi,

We don't have any python script for device that's running host test. You can just use simple_central project to connect to your peripheral and then in the SW, the MTU_exchange will be executed.

May I ask why wouldn't you just run simple_central or use btool?

0 Siva Krishna Kattinti over 8 years ago in reply to Christin Lee

Expert 1090 points

It's just my interest to run automatically via python instead of manually running via bTool.
Anyway thanks so much for providing the information.
This answers my question.

Thanks,
Siva.

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Starterware/CC2640R2F: CC2640R2F Changing MTU size