User's Guide

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The Join Process Control command allows the software to initiate or stop
the secure JOIN process. It has the following subcommands.
These operations are equivalent to the push-button initiated operation.
If a JOIN operation is started by the serial command (CMD:JOINCTL[2]),
push-button operation is ignored until the JOIN operation finishes.
Register write operations are inhibited when a JOIN process is active
except that a Halt JOIN command is never inhibited. A Halt JOIN operation
completes before the ACK is sent.
When the JOIN operation is started the KEYRCV flag in the SECOPT
register determines whether the module is a master or slave and whether
a key can be sent or changed. The JOIN process uses and modifies the
non-volatile address registers.
The Write Key command writes a 16-byte AES key to the selected key
register. As with most of the registers, the encryption key has both volatile
and non-volatile registers. The volatile register is used during run time, but
is lost on a power cycle or reset. When the module powers up, the volatile
register is loaded from the non-volatile register. This makes the non-volatile
register value the default on power-up.
The key value of all zero bytes is reserved as a “no key” indication.
Figure 92 shows the command for writing the AES key to the module.
If KeyN is 0x01, the command writes to the volatile key register. If it is 0x02,
it writes to the non-volatile key register.
HumPRO
TM
Series JOINCTL Subcommand Values
Subcommand Value Operation
0 Halt JOIN operation
1
Generate a random network key and address. This sets the
module as the network master (SECOPT:KEYRCV=0)
2 Perform the JOIN operation with another module
Figure 91: HumPRO
TM
Series JOINCTL Subcommand Values
Figure 92: HumPRO
TM
Series Transceiver Write Key Command
HumPRO
TM
Series Write Key Command
Write Command
Header Size Escape Address Value KeyN Key0 ... Key15
0xFF Size 0xFE 0x47 0x11 KeyN Key0 ... Key15
The Clear Key command sets the selected key to all zeros. Figure 93
shows the structure of this command.
If KeyN is 0x01, the command writes to the volatile key registers. If it is
0x02, it writes to the non-volatile key registers.
The Reload Key command copies the key in non-volatile memory (NKN)
to the volatile location (NKV). This allows a sophisticated system to change
the keys during operation and quickly revert back to the default key.
The Non-volatile Reset command (FF 07 FE 47 20 FE 2A FE 3B) sets
all non-volatile registers to their default values. When the configuration is
reset, the following message, shown in quotes, is sent out the UART at the
current baud rate, then the module is reset, similar to a power cycle:
“\r\nConfiguration Reset\r\n”.
This reset can also be done by toggling the PB line as described in the
Restore Factory Defaults section.
Figure 93: HumPRO
TM
Series Transceiver Clear Key Command
HumPRO
TM
Series Clear Key Command
Write Command
Header Size Escape Address Value KeyN
0xFF 0x04 0xFE 0x47 0x12 KeyN