Sierra Wireless DART 300 User Manual

Feature Reference 

 

DART 300 Modem 

 

Page 58 

 

2110212 Rev 1.0 

In summary, the Auto-register NEI Index value will follow the Active NEI Index value if there is 
an attempt to register manually.  The Active NEI Index can change freely and is not influenced by 
changes in the Auto-register NEI Index. 

This is the default setting from the factory and is highly recommended. 

The modem can be set to register the NEI indexed by +WS176 (Auto-register NEI Index) 
automatically.  Register +WS173 (Registration Mode) controls this feature.  When the mode 
register is set to 1 the modem will immediately attempt to register and will subsequently attempt 
to register automatically on start-up or reset. 

The default setting of the modem from the factory is to auto-register NEI index 1 (both registers 
set to 1).  The modem will always retain changes to both registers without the need to save the 
settings explicitly (&W).  Whenever the modem is reset or power-cycled it will resume operation 
with the last-used settings. 

Automatic registration will retry indefinitely, scanning for a new channel each time, should 
attempts fail. 

Setting the Registration Mode to 0 will de-register the current NEI if it successfully auto-
registered earlier. 

When the modem is set for manual registration (+WS173=0) it will not attempt to locate a CDPD 
channel until commanded to register (+WPREG or a dial command D) or the command to set a 
channel (+WPCHAN) is set to 0 (automatic selection).  As noted in the previous section, you may 
select a channel first in network diagnostic situations.  If you do not force automatic channel 
selection by setting +WPCHAN=0, the modem will scan for one when the registration command 
is issued. 

To register an NEI manually: 

1.  +WS197=n where n is the index to the NEI you wish to register. 

2.  +WPREG to register the NEI.  If the NEI is currently registered the modem takes no action 

and returns the registration result code.  Otherwise, the modem will: 

•  De-register any currently registered NEI 
•  Acquire a channel if necessary (and if not forced to a specific channel) 
•  Attempt to register the NEI and authenticate credentials 

The modem will terminate the process on one of three conditions: 
•  Success – The modem will give the REGISTERED response, then the OK result code. 
•  Failure – The CDPD network failed to register the NEI for reasons given in the response 

(i.e. INSUFFICIENT_CREDENTIALS), followed by the OK result code. 

•  Time-out – The register +WS198 (Registration Wait Time) allows settings from 1 to 255 

seconds (default 30) for the registration process.  If this time elapses without successful 
registration the modem will return the TIMEOUT_EXPIRED response, then the OK result 
code. 

Data Carrier Detect (DCD) is tied to sessions not network registration.  A session does not begin 
until you originate a (client) session or answer one (as a server).