Linx HumPRC Series Data Manual page 16

A module becomes a node by joining with an administrator. This is done
by pressing and releasing the PB button on both units. The modules
automatically search for each other using a special protocol. When they
find each other, the administrator sends the node the encryption key,
UMASK and its network address. The UDESTID is set to the address of the
administrator. The values are encrypted using a special factory-defined key.
Once the Join Process is complete, the MODE_IND blinks on both units
and they now operate together. This is shown in Figure 22 A.
If UMASK is pre-set when Generate Key is initiated, then the Join Process
uses that mask and sets the address accordingly. This can allow more
nodes in the network. This is shown in Figure 22 B. Likewise, the network
key can be written to the module with the CDI interface. If the PGKEY
bit in the SECOPT register is also set to 0, the Generate Key process
will generate a network address without changing the preset key. Or the
administrator can be completely configured through the CDI and the
Join Process used to associate nodes in the field. This gives the system
designer many options for configuration.
The SECOPT register is used to configure options related to the Join
Process. This allows the OEM to set desired values at the factory and allow
final network configuration in the field. This includes disabling the ability to
change the address, change the key, share the key or perform a factory
reset through the PB line. The built-in security prohibits changing a node to
an administrator without changing the key.
Please see Reference Guide RG-00107, The HumPRO
Process for more details and examples of the Join Process.
Series Join
TM
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A) Key Generation and Network Join from Factory Default
Generate Key
D
UMASK = FF FF FF FF
USRCID = FF FF FF FF
UDESTID = FF FF FF FF
No Key
D
UMASK = FF FF FF FF
USRCID = FF FF FF FF
UDESTID = FF FF FF FF
No Key
A
UMASK = 00 00 00 FF
USRCID = 76 54 32 00
UDESTID = 76 54 32 FF
Network Key
B)
Key Generation and Network Join from Preset Mask
Generate Key
P
UMASK = 00 00 0F FF
USRCID = FF FF FF FF
UDESTID = FF FF FF FF
No Key
D
UMASK = FF FF FF FF
USRCID = FF FF FF FF
UDESTID = FF FF FF FF
No Key
A
D = Factory Default
UMASK = 00 00 0F FF
A = Network Administrator
USRCID = 76 54 30 00
N = Network Node UDESTID = 76 54 3F FF
Network Key
P = OEM Preset Unit
Figure 22: HumPRC Series and HumPRC Series Join Process Examples
TM TM
A
UMASK = 00 00 00 FF
USRCID = 76 54 32 00
UDESTID = 76 54 32 FF
Network Key
JOIN
N
UMASK = 00 00 00 FF
USRCID = 76 54 32 01
UDESTID = 76 54 32 FF
Network Key
A
UMASK = 00 00 0F FF
USRCID = 76 54 30 00
UDESTID = 76 54 3F FF
Network Key
JOIN
N
UMASK = 00 00 0F FF
USRCID = 76 54 30 01
UDESTID = 76 54 3F FF
Network Key
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27