Technical information

W24 RAS Server
2-84 AT+i Commands Reference Manual May 31, 2008
Lost Carrier
When W24 is online as a result of a RAS connection and the carrier signal is lost (due to an error
or due to the PPP client closing the connection), W24 checks if the host used the PPP connection
(tried to open an Internet session) during the connection. If the host did not use the connection, or
W24 was in SerialNET mode, W24 silently performs a software reset and no indication of the
disconnection is given to the host. Otherwise, if the host did use the connection, W24 acts as if
this is a regular session created by the host that was terminated with a lost carrier signal. The error
code is returned to the host on the next command that requires the use of the connection and only
then will a software reset be performed.
Restrictions
Modem RING strings are not detected while the baud rate between W24 and the host is not yet
established. This means that in order to use the RAS feature, one of the following must apply:
• BDRF is set to a fixed value (3-9 or h).
• W24 is in SerialNET mode with its baud rate defined by the SNSI parameter.
• An a or A was previously received from the host serial port and W24 has determined the
host's baud rate.
In addition, Modem RING strings are not detected when W24 is in Modem Command (MCM)
mode.