Adding Service Change Characteristic

Thomas Rauturau

Other Parts Discussed in Thread: WL1837MOD, WL1837

Hello,

I use wl1837mod with blutopiaPM.

I added one attribute to my BLE custom service, but i didn't see my new characteristic on my iphone (device bonded, paired).
When I reboot the iphone, I can finally see my new characteristic.

To force iphone to refresh characteristic table, I must add Service Changed (UUID 0x2A05) in Generic Attribute (0x1801)

But Generic Attribute service is a bluetopia service (created by the stack), not manageable by the Platform Manager.

question:
how can I force my iphone to refresh its services?
if yes, how to set it?

Best regards,

Thomas.

over 5 years ago

0 Vihang Parmar over 5 years ago

TI__Mastermind 29250 points

Hi Thomas,

Could you please provide the btsnoop logs of BluetopiaPM for this scenario?

Best regards,

Vihang

0 Thomas Rauturau over 5 years ago in reply to Vihang Parmar

Intellectual 440 points

Hi Vihang,

I cut the log into 3 parts (zip) :

1_pairing

I connect my iphone to the wl1837 for the firt time.

A pairing process is launched (6 numbers code)

All is ok.

2_add_new_characteric

I add a new characteristic in my wl1837 application.

I update my wl1837

I connect my iphone (always paired) but I don't see my new characteristic

3_after_iOS_reboot

I reboot my iphone, and I can see the new charactristic.

Thank you for your analysis

Thomas

2705.log.zip

0 Hari Nagalla over 5 years ago in reply to Thomas Rauturau

TI__Mastermind 27080 points

It appears, iPhone is not querying for the service characteristics. Only on a reboot it seems to querry for the service attributes.. Did, you try with Android devices?

Thanks

0 Thomas Rauturau over 5 years ago in reply to Hari Nagalla

Intellectual 440 points

Hi Hari,

yes it's the same behavior with Android.

But the question is how to use Service Changed (UUID 0x2A05) in Generic Attribute (0x1801) with Blutopia Platform Manager ?

This problem blocks the phone application development.

https://www.bluetooth.com/specifications/gatt/viewer?attributeXmlFile=org.bluetooth.characteristic.gatt.service_changed.xml

Best regards,

Thomas.

0 Hari Nagalla over 5 years ago in reply to Thomas Rauturau

TI__Mastermind 27080 points

Hi Thomas,

Did, you try using the below GATT Api, to indicate Service change:

BTPSAPI_DECLARATION int BTPSAPI GATT_Service_Changed_Indication ( unsigned int BluetoothStackID,
unsigned int ConnectionID,
GATT_Service_Changed_Data_t * Service_Changed_Data
)

You, may refer Blutopia Doxygen from the latest release..

Thanks

0 Thomas Rauturau over 5 years ago in reply to Hari Nagalla

Intellectual 440 points

Hi Hari,

Thank for for answer.

How can I use GATT_Service_Changed_Indication() from a bluetopia Plaform Manager client?

or more generally, how can I handle my GATT service from my client?

Best regards,

Thomas.

0 Hari Nagalla over 5 years ago in reply to Thomas Rauturau

TI__Mastermind 27080 points

Hi Thomas,

In general, if there is no corresponding PM command, you can use "DEVM_SendRawHCICommand" to send the HCI command.. Please, check the Blutopia Doxygen to get the API details:

Thanks

BTPSAPI_DECLARATION int BTPSAPI DEVM_SendRawHCICommand
( unsigned char OGF,
unsigned short OCF,
unsigned char CommandLength,
unsigned char CommandData[],
unsigned char * ResultStatus,
unsigned char * ResultLength,
unsigned char * ResultBuffer,
Boolean_t
WaitForResponse
)
The following function is provided to allow a mechanism for local modules to send raw HCI commands to the Bluetooth Device.
Parameters
OGF Opcode Group Field value – upper 6 bits of the opcode field (e.g., 0x01 for Link Control commands).
OCF Opcode Command Field value – lower 10 bits of opcode.
CommandLength Length of the valid data in Command_Data.
CommandData Array of bytes that make up the command
ResultStatus Pointer to a byte to receive a returned status.
ResultLength This parameter is both an input and output parameter. On input this parameter should contain the total length (in bytes) of the buffer that is pointed to by the BufferResult parameter. On successful return from this function this will contain the length of the valid data returned in the BufferResult.
ResultBuffer Pointer to an array of bytes for the command result.
WaitForResponse TRUE if the function should wait for the result, FALSE otherwise.
Returns
This function returns zero if successful, or a negative return error code if there was an error.

0 Fabien THOMAS over 5 years ago in reply to Hari Nagalla

Prodigy 30 points

Hello,

I work with Thomas and we would like to know which HCI command and group filed value is used by GATT_Service_Changed_Indication() ?

Thank you.

0 Thomas Rauturau over 5 years ago in reply to Fabien THOMAS

Intellectual 440 points

Hello,

Honestly I don’t think an HCI command could solve my problem. But if you think so, thank you for giving me the exact command (OGF and OCF).

I wish to have paid support. How can I do ?

Thank you.

0 Hari Nagalla over 5 years ago in reply to Thomas Rauturau

TI__Mastermind 27080 points

Hi Thomas,

I will look into today and get back.. I was distracted, due to other resources on holidays and other work.. My comment on RawHCICommand, was for in general when corresponding HCI command is not available in Bluetopia PM (but available in Bluetopia).. I will look into this today and get back.. Sorry for the delay..

Thanks

0 Thomas Rauturau over 5 years ago in reply to Hari Nagalla

Intellectual 440 points

Thank You Hari.

0 Hari Nagalla over 5 years ago in reply to Thomas Rauturau

TI__Mastermind 27080 points

Hi Thomas,

I thought, i replied to this thread.. Seems, it was not saved.. Anyways, It turns out with BluetopiaPM, the stack is supposed to automatically sends the "service changed" indication on a database change. It is a build option, and due to some reason it was not turned on by default. I will send a link to a BluetopiaStack with this enabled to try..

Thanks

0 Thomas Rauturau over 5 years ago in reply to Hari Nagalla

Intellectual 440 points

Thank you Hari.

I will try this new stack this week.
I compared this new stack with mine, but I don't see the build option.
Could you tell me the name of this option, please?

Thanks

0 Hari Nagalla over 5 years ago in reply to Thomas Rauturau

TI__Mastermind 27080 points

Hi Thomas,

No changes are needed at the application build. The build option was for stack and it is built with the option enabled. Just, give it a try and take BT snoop logs..

Thanks

0 Hari Nagalla over 5 years ago in reply to Hari Nagalla

TI__Mastermind 27080 points

Hi Thomas,

Did, you try the new build? I will close this thread for now..

Thanks

0 Thomas Rauturau over 5 years ago in reply to Hari Nagalla

Intellectual 440 points

Hi Hari,

Yes, I tested with the new build. the GATT service changed event was send from my wl1837.

And I saw it on the HCI log on the Android phone.

It's more complicated with iOS. I will continue to test it.

Thank you.

Thomas

refreshAndroid.zip

0 Hari Nagalla over 5 years ago in reply to Thomas Rauturau

TI__Mastermind 27080 points

Hi Thomas,

Alright. I will close the thread for now. If there is an issue please raise a new thread..

Thanks

0 Thomas Rauturau over 5 years ago in reply to Hari Nagalla

Intellectual 440 points

Hi Hari,

I managed to refresh the list of services with iOS.

For information, To access the charateristics, you must necessarily be bonded.

Thank you for the build option

Thomas.

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Adding Service Change Characteristic