N O V A T E L W I R E L E S S T E C H N O L O G I E S L T D .
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A T C o m m a n d S p e c i f i c a t i o n - E x p e d i t e a n d M e r l i n
W i r e l e s s I P M o d e m s
Line Speed and Format
Description:
This command allows the user to specify the data bit rate or “line speed” and format of the host serial port
for all subsequent communications. Some applications have the need for operating at a different line
speed, other than 9600, because of existing or established wire-line software. The line speed change will
not take effect until the registers have been saved and the modem reset.
Format:
ATS23?
To determine the current line setting
OR
AT&L?
To determine the current line setting
ATS23=<S>,<D><P><N>
To change the serial port settings
OR
AT&L<S>,<D><P><N>
To change the serial port settings
Where:
<S> = Baud rate in bits/second: [1200 | 2400 | 4800 | 9600 | 19200]
<D> = Number of data bits [7 | 8]
<P> = Parity [O | E | N]
<N> = Number of stop bits [1 | 2]
Examples (all have 8 bits, no parity, 1 stop bit)
For 19200 enter
AT&L19200,8N1
For 9600 enter
AT&L9600,8N1
For 4800 enter
AT&L4800,8N1
For 2400 enter
AT&L2400,8N1
For 1200 enter
AT&L1200,8N1
Default Setting
9600,8N1
Note:
When AT&L is entered the modem will interpret this as AT&L1200,7O1 (7 bits, odd parity, 1 stop)
Validity:
This command is valid only in Program Mode. Serial port change will not occur until settings are saved
and a soft reset occurs.
Other Considerations:
The NRM does not support the auto-baud detection function. Characters received with parity errors are
ignored by the NRM with no indication to the Host.
