Register S36-Baud Rate Adapting; Register S51-Delay Until Modem Pool Activation; Register S52 Through S54-Product Code Response; Register S66-Hayes/Keyboard Dialing Autobaud Interpretation - Nortel Meridian SL-100 Reference Manual

three characters must be of shorter duration than that specified for the guard
time.
Register S36—baud rate adapting
When an attempt to make a connection fails due to incompatible baud rates,
the MCA reads this register to determine whether to terminate the
connection, or to adapt to the far end baud rate. If S36 is set to 0, the MCA
hangs up if the baud rates are incompatible. If S36 is set to 1 and the MCA
is the answering party, then the MCA adapts to the calling party's baud rate.
Register S51—delay until modem pool activation
S51 holds the value of delay before outbound modem pool activation. Each
decimal increment of S51 represents a 0.25-second delay. This register is
not altered by the software reset commands.
Register S52 through S54—product code response
These three registers contain the product identification code and are output
in response to the I0 command. The default is 960 (Smartmodem V-series
960 modem). Other possible values are: 124 (Smartmodem V-series 1200),
240 (Smartmodem 2400 V-series 2400). These registers are not altered by
the software reset commands.
Register S66—Hayes/keyboard dialing autobaud interpretation
S66 defaults to the value sent in the operating parameters download set up
by the user. If no download of operating parameters occurs, the default
value is zero (Hayes keyboard dialing).

Hayes keyboard dialing command syntax

All Hayes commands are prefixed by AT and followed by a carriage return.
The carriage return executes the AT command. The repeat previous
command (A/) is the only exception to the command line structure; it is sent
without the AT prefix and must appear on a line by itself. The MCA
examines the AT prefix and automatically determines the baud rate and
parity settings of the data terminal equipment. Both letters of the AT prefix
must be entered using all upper case or all lower case (at or AT). The MCA
does not recognize an upper case A and a lower case t (At) or the reverse
combination (aT).
Each command line can contain a number of commands concatenated
together. However, each line is limited to a maximum of 40 characters
(excluding the AT). Some commands must be entered on a line by
themselves as they prevent other commands on the same line from being
processed. Most AT commands have selectable numeric parameters. For
example, E0 turns off character echo, while E1 turns it on. Punctuation
characters (- or ,) are allowed for readability, but take up space in the
Meridian SuperNode MSL-100 Meridian Modular Telephones Reference Manual MSL11
Hayes keyboard dialing 9-7