Example: Deregister a previously registered device

This feature is only needed in a distributed trust center, because the key table entries are persistent and stored in flash. In a distributed trust center, there are only a limited number of entries available, proper management of the key table is required if more than 10 devices will be joining using registration.

To deregister a device, issue a 0x24 registration frame on the trust center with the serial number of the registered device and a null (blank) key.

Deregistration example

A device with the serial number 0013A200 12345678 that was previously registered has successfully joined the network, and needs to be deregistered to make room for subsequently joining devices.

The following 0x24 frame is generated and passed into the UART of the trust center. Note, that there is no key field, indicating that the key entry should be removed:

7E 00 0D 24 C4 00 13 A2 00 12 34 56 78 FF FE 00 51

The trust center will respond with the following 0xA4 registration response frame:

7E 00 03 A4 C4 00 86

Note The Frame ID (0xC4) in the response corresponds with the Frame ID of the registration attempt. A 00 result indicates that the key was successfully removed from the table.