XC09-009-DK Digi International/Maxstream, XC09-009-DK Datasheet - Page 25

• Manufacturer Part Number: XC09-009-DK
• Description: KIT DEV FOR 900MHZ 9600BPS 1MW
• Manufacturer: Digi International/Maxstream
• Series: XCite™r
• Type: Transceiverr

Specifications of XC09-009-DK

• Frequency: 900MHz
• For Use With/related Products: XCite Module (900 MHz, 9600 bps) US and Canada
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

9XCite™ OEM RF Module – Product Manual v2.1 [2007.01.04]
LH (Wake-up Initializer Timer) Parameter
<Non-AT Settable Parameter: Sleep (Low Power)> LH Parameter adjusts the duration of time in
which the wake-up initializer is sent. When receiving modems are put into the Cyclic Sleep Mode,
they power-down after a period of inactivity (specified by ST (Time before Sleep) Parameter) and
will periodically awaken and listen for transmitted data. In order for the receiving modems to ini-
tialize with the transmitter, they must detect ~35ms of the wake-up initializer. LH Parameter must
be used whenever a receiver is operating in Cyclic Sleep Mode. This lengthens the wake-up initial-
izer to a specific amount of time (in x 100 ms). The long wake-up initializer must be longer than
the cyclic sleep time that is determined by SM (Sleep Mode) Command. 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. The following data and figures illustrate this behavior:
Parameter Range: 0 - 0xFF [x 100 ms]
# of bytes returned: 1
Default Parameter Value: 0x01 (0.1 second)
Related Parameters: HT (Time before Wake-up Initializer), SM (Sleep Mode), ST (Time before
Sleep)
Figure 3‐01. Correct Configuration (LH > SM)
The length of the wake-up initializer exceeds the time interval of Cyclic Sleep. The receiver is guar-
anteed to detect the wake-up initializer and receive the accompanying payload data.
Figure 3‐02. Incorrect Configuration (LH < SM)
The length of the wake-up initializer is shorter than the time interval of Cyclic Sleep. This configu-
ration is vulnerable to the receiver waking and missing the wake-up initializer (and therefore also
the accompanying payload data).
© 2007 MaxStream, Inc.
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