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Command descriptions
9XTend-PKG-R RS-232/485 RF Modem User Guide
49
In order for modems to communicate with each other, the modems must have the same channel number since each
channel uses a different hopping sequence. Different channels can be used to prevent modems in one network from
listening to transmissions of another.
HT (Time before Wake-up Initializer) Command
<Sleep (Low Power)> The HT command is used to set/read the time of inactivity (no serial or RF data is sent or
received) before a wake-up initializer is sent by a TX (transmitting) RF modem. The HT parameter should be set
shorter than inactivity timeout [ST Command] time of any RX (receiving) modems operating in Cyclic Sleep (SM=4-8).
The wake-up initializer sent by the TX modem instructs all RX modems to remain awake to receive RF data.
From the RX modem perspective: After HT time elapses and the inactivity timeout [ST Command] is met, the RX
modem goes into cyclic sleep. In cyclic sleep, the RX modem wakes once per sleep interval [SM Command] to check
for a wake-up initializer. When a wake-up initializer is detected, the modem stays awake to receive data. The wake-up
initializer must be longer than the cyclic sleep interval to ensure that sleeping modems detect incoming data.
When HT time elapses, the TX modem knows it needs to send a wake-up Initializer for all RX modems to remain awake
and receive the next transmission.
HV (Hardware Version) Command
<Diagnostics> The HV command is used to read the hardware version of the RF modem.
AT Command: ATHP
Binary Command: 0x11 (17 decimal)
Parameter Range: 0 - 9
Default Parameter Value: 0
Number of bytes returned: 1
Related Commands: ID (Modem VID), DT (Destination Address), MK (Address Mask)
AT Command: ATHT
Binary Command: 0x03 (3 decimal)
Parameter Range:0 - 0xFFFF [x 100 milliseconds]
Default Parameter Value: 0xFFFF (wake-up initializer will not be sent)
Number of bytes returned: 2
Related Commands: LH (Wake-up Initializer Timer), SM (Sleep Mode), ST (Time before Sleep)
AT Command: ATHV
Parameter Range:0 - 0xFFFF [Read-only]
Legacy Modem Minimum Firmware Version Required: v1.x80