HT (Time before Wake-up Initializer)

This command applies to the XTC RF Module.

Sets or displays the time of inactivity (no serial or RF data is sent or received) before a transmitting (TX) RF device sends a wake-up initializer. The main purpose of this command is to prevent devices from sending the Long Header with every data packet. For more information on long headers, see LH (Wakeup Initializer Timer).

For RX devices operating in Cyclic Sleep mode (SM = 4-8), set HT to be shorter than the ST command.

The TX device sends a wake-up initializer, which instructs all receiving (RX) devices to remain awake to receive RF data.

From the perspective of the RX device: after HT time elapses and the inactivity timeout (ST command) is met, the RX device goes into cyclic sleep. In cyclic sleep, the RX device wakes once per sleep interval (SM command) to check for a wake-up initializer. When it detects a wake-up initializer, the device stays awake to receive data. The wake-up initializer must be longer than the cyclic sleep interval to ensure that sleeping devices detect incoming data.

When HT time elapses, the TX device knows it needs to send a wake-up initializer for all RX devices to remain awake and receive the next transmission.

Binary command

0x03 (3 decimal)

Parameter range

0 - 0x53E2, 0xFFFF [x 100 ms]

Default

0xFFFF (wake-up initializer will not be sent)

Bytes returned

2