Wavenet Technology Pty Ltd. BM2900D 用户手册

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Boomer II User Manual & Integrator’s Guide _________________________________________________Installation 
 
BM210012WT37 
47 
Copyright Wavenet Technology © November 2003 
Some applications require the use of group LLIs, such as a stock 
quotation broadcast service. Each active group LLI (in addition to the 
modem's factory loaded individual LLI) increases the percentage of 
time the modem stays in the receive state, thereby increasing its overall 
current consumption. 
Roaming Time 
The amount of time the modem spends scanning a channel or roaming 
to a new channel will affect the current consumption. The current 
consumption is dependant on the Network type  (Private or Public) and 
the System type (MFR or SFR). 
Power Control 
The host/terminal provides the supply rail (HOST 3.8V) to the modem 
through the Data Interface Connector.  
The host/terminal turns the modem ON by asserting the 
HOSTPWR_ON signal. 
The host/terminal may request the modem to turn OFF by de-asserting 
the HOSTPWR _ON or by sending a specific NCL command across 
the serial interface. For the modem to turn OFF after an NCL request 
the HOSTPWR_ON signal must be de-asserted. 
ESD protection is provided on all power supply lines and I/O lines. 
Power-Up Sequence 
Reference should be made to the Power-UP Timing Diagram below 
when reading the following Power-UP Sequence description. 
To turn the modem ON, power must be applied (HOST 3.8V) and the 
host/terminal asserts the HOSTPWR_ON signal.   
The modem contains an internal voltage detector and reset delay circuit 
to generate a reset signal for the CPU to ensure orderly and reliable 
software initialisation. 
An externally controllable reset signal (HCRESET) is optionally 
available if the host/terminal wants reset synchronisation or to force a 
modem reset while power is still applied.  
If the HCRESET signal is used, once it is de-asserted the modem CPU 
will be able to initialise.  
Once out of reset the first operation is the boot-up of the modem CPU. 
At this time CTS is momentarily asserted, then de-asserted. After a 
successful boot up, the CPU starts the modem initialisation sequence. 
After the initialisation sequence, the Native Mode interface and the 
serial interface are active.  
Following successful initialisation, the modem asserts DSR and 
performs the initialisation protocols for both the DTE interface and the 
RF network. After successfully initialising the DTE interface, the 
modem asserts CTS. After the network ACK of the registration 
sequence, DCD is asserted.