Digi XBEE-PRO S3B Manual

XBee‐PRO®900HP/XBee‐PRO®XSCRFModules
©2014DigiInternationalInc. 106
until no data is detected for the period of time specified by the ST Command, at which point it resumes its
low-power cyclic state.
Note: The cyclic interval time defined by SM (Sleep Mode) Command must be shorter than the interval time
defined by LH (Wake-up Initializer Timer).
For example: If SM=4 (Cyclic 1.0 second sleep), the LH Parameter should equal 0x0B ("1.1" seconds). With
these parameters set, there is no risk of the receiving module being asleep for the duration of wake-up
initializer transmission. “Cyclic Scanning” explains in further detail the relationship between “Cyclic Sleep” and
“Wake-up Initializer Timer”
Cyclic Scanning. Each RF transmission consists of an RF Initializer and payload. The wake-up initializer
contains initialization information and all receiving modules must wake during the wake-up initializer portion
of data transmission in order to be synchronized with the transmitting module and receive the data.
CorrectConfiguration(LH>SM)
Lengthofthewake‐upinitializerexceedsthetimeintervalofCyclicSleep.Thereceiverisguaranteedtodetect
thewake‐upinitializerandreceivetheaccompanyingpayloaddata.
IncorrectConfiguration(LH<SM)
Lengthof
wake‐upinitializerisshorterthanthetimeintervalofCyclicSleep.Thisconfigurationisvulnerableto
thereceiverwakingandmissingthewake‐upinitializer(andthereforealsotheaccompanyingpayloaddata).
Command Mode
To modify or read module parameters, the module must first enter into Command Mode, the state in
which received characters on the UART are interpreted as commands. Two command types are avail-
able for programming the module:
• AT Commands
• Binary Commands
For modified parameter values to persist in the module registry, changes must be saved to non-vola-
tile memory using WR (Write) Command. Otherwise, parameters are restored to previously saved val-
ues after the module is powered off and then on again.
AT Commands
To Enter AT Command Mode:
• Send the 3-character command sequence “+++” and observe guard times before and after
the command characters. [refer to ‘Default AT Command Mode Sequence’ below.] The ‘Termi-

Digi XBEE-PRO S3B Specifications

General

Brand	Digi
Model	XBEE-PRO S3B
Category	Control Unit
Language	English