User Guide

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SECOPT - Security Options
Volatile Address = 0xD4; Non-Volatile Address = 0x84
This register selects options for security features.
Each bit in the register sets an option as shown in Figure 85. Unlike other
registers, the non-volatile register (0x84) affects all Join operations. The
EN_UNENC bit in the volatile register affects data packet reception.
When PB_RESET is 1 the Factory Reset function is enabled from the PB
input. This allows a user to reset the module configurations back to the
factory defaults with 4 short presses and a 3 second hold of a button
connected to the PB input.
When PSHARE is 1 the Share Network Key function is enabled during the
Join Process. This allows an administrator to share the encryption key it
created. When 0, a Join Process sends the network address, but no key.
Figure 84: HumPRC
TM
Series Transceiver Packet Options Command and Response
HumPRC
TM
Series Security Options
Read Command Read Response
Header Size Escape Escape Address ACK Address Value
0xFF 0x03 0xFE 0xFE
0x54
0x04
0x06
0xD4
0x84
V
Write Command
Header Size Escape Address Value
0xFF 0x03 0xFE
0x54
0x04
V
HumPRC
TM
Series Transceiver Security Option Codes
Bit Name Description
0 PB_RESET Permit factory reset from PB input sequence
1 PSHARE Permit key sharing
2 PGKEY Permit clearing key and changing key
3 CHGADDR Permit changing an address
4 KEYRCV
1: Receive key and address during Join Process (node)
0: Send key and address during Join Process (admin)
5 EN_UNENC Enable receiving unencrypted packets
6 Reserved Reserved (must be 1)
7 EN_CHANGE Enable changes to security options
Figure 85: HumPRC
TM
Series Transceiver Security Option Codes
When PGKEY is 1 the Join Process is allowed to change or clear the
network key. The key can always be changed through serial commands.
When CHGADDR is 1 the Join Process is allowed to generate a random
network address if the module is an administrator. If the module is a node it
is allowed to accept an address assignment from the administrator.
When KEYRCV is 1 the module is set to receive a network key from an
administrator and act as a node. When it is 0, the module is set as an
administrator and sends a network key and assigns an address to the
node.
In order for this bit to change from 1 to 0, both volatile and non-volatile
copies of the network key must be cleared, preventing nodes from being
manipulated to transmit the key. This bit is cleared by the GENERATE_KEY
push-button function.
When EN_UNENC is 1 the module accepts unencrypted packets. If this bit
is 0, unencrypted received packets are ignored.
When EN_CHANGE is 1, changes are permitted to the SECOPT register,
except as noted for KEYRCV changes.
Clearing this bit prohibits the following SECOPT changes to enhance
security:
1. changing PSHARE from 0 to 1
2. changing EN_CHANGE from 0 to 1.
3. changing EN_UNENC from 0 to 1.
An attempt to make a prohibited change causes a NACK command
response.
When EN_CHANGE is 0, these restrictions can only be removed by
resetting the module configuration to the factory default.