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Command descriptions
9XTend-PKG-R RS-232/485 RF Modem User Guide
50
ID (Modem VID) Command
<Networking and Security> The ID command is used to set/read the VID (Vendor Identification Number) of the RF
modem. RF modems must have matching VIDs in order to communicate.
KY (AES Encryption Key) Command
<Networking and Security> The KY command is used to set the 256-bit AES (Advanced Encryption Standard) key for
encrypting/decrypting data. Once set, the key cannot be read out of the modem by any means. The entire payload of
the packet is encrypted using the key and the CRC is computed across the ciphertext. When encryption is enabled,
each packet carries an additional 16 bytes to convey the random CBC Initialization Vector (IV) to the receiver(s). The
KY value may be “0” or any 256-bit value (= 64 hex digits = 32 bytes). Any other value, including entering ATKY by itself
with no parameters, causes an error.
A modem with the wrong key (or no key) will receive encrypted data, but the data driven out the serial port will be
meaningless. Likewise, a modem with a key will receive unencrypted data sent from a modem without a key, but the
output will be meaningless. Because CBC mode is utilized, repetitive data appears differently in different
transmissions due to the randomly-generated IV.
LH (Wake-up Initializer Timer) Command
<Sleep (Low Power)> The LH Command is used to set/read the duration of time during which the wake-up initializer is
sent. When receiving modems are in Cyclic Sleep Mode, they power-down after a period of inactivity (as specified by
the ST parameter) and will periodically wake and listen for transmitted data. In order for the receiving modems to
remain awake, they must detect ~35ms of the wake-up initializer.
LH Command must be used whenever a receiving modem is operating in Cyclic Sleep Mode. The Wake-up Initializer
Time must be longer than the cyclic sleep time that [as determined by SM (Sleep Mode) parameter]. If the wake-up
initializer time were less than the Cyclic Sleep interval, the connection would be at risk of missing the wake-up
initializer transmission.
AT Command: ATID
Binary Command: 0x27 (39 decimal)
Parameter Range:
0x11 - 0x7FFF (user-settable)
0 - 0x10 and 0x8000 - 0xFFFF (factory-set)
Default Parameter Value: 0x3332 (13106d)
Number of bytes returned: 2
AT Command: ATKY
Binary Command: 0x3C (60 decimal)
Parameter Range: 0 - (any other 64-digit hex valid key)
Default Parameter Value: 0 (disabled)
Number of bytes returned: 2
Number Base: Always Hexadecimal