zigbee callback ZB_ZCL_REGISTER_DEVICE_CB using different cb ID values

[Robert]

I been having an issue using the ZB_ZCL_REGISTER_DEVICE_CB to know when the ZC writes to an attribute that is of type 0x42 String type. It seems that the callback id changes depending on the length of the string I write to the device.

I started with the light bulb example and a CLI example. The CLI is configured as the ZC and the light bulb (ZR) joins the ZC. When I write to the basic cluster (0x00) attr location (0x10) using 0x42 data type, I see the callback ID change based on the string size I use to send to the light bulb.

For an example if I write one char the ID is 66 and if I write 2 chars I see an ID of 10 and if I do 7 chars I see an ID of 0. (I thought I would always see an ID of 0 since that is defined as ZB_ZCL_SET_ATTR_VALUE_CB_ID, instead of ZB_ZCL_IAS_WD_SQUAWK_VALUE_CB_ID (10) )

Is there anther way I should be listening of a write attr on a ZR device?

[Marjeris Romero]

Hi,

I need to inspect a bit more about why this is happening. I don't think the zcl_device_cb_id changes because of the string size, when I tested it seemed to depend on what has been written from before, etc, it seems very random. I also expected to get ZB_ZCL_SET_ATTR_VALUE_CB_ID as the callback ID but perhaps I am missing something. I have made an internal inquiry with our Zigbee developers about this behaviour, so I will come back to you next week with more answers

BR,

Marjeris

[Robert]

Thank you, for now I have been using the string size to know if it has been updated. (I am now checking the string size in that call back and if it has changed then I act on it and reset it back to 0 till I hear back on how to act on receiving a string since the string has never been corrupt and has been the correct value that was written)

Looking forward to hearing back.

[Marjeris Romero]

Hi Robert,

I am sorry for the delay here. I am still waiting for an answer from our developers. Because of vacation time we have had low staffing in July but things should be getting back to normal now.

Let me know if there are some news on this ticket from your side.

Best regards,

Marjeris

[Robert]

Nothing as of right now, I have just been using a work around to get around this.

Looking at the string size and when it is different, than I now that value has changed so I run the function I need and clear the string size.

[Marjeris Romero]

Hi,

Just wanted to update the ticket. Based on this case our developers found a bug in ZCL, it makes all attributes with the "string" type unusable and can lead to unexpected ZCL callbacks. Currently a workaround could be to set all attributes that have "octet string" or "character string" type as read only, but it's difficult to do something with the ZBOSS defined attributes...

DSR (the ZBOSS stack provider) has been informed about the bug, perhaps they can see a workaround for this issue or solution for a next release. Thanks for reporting. 

Best regards,

Marjeris