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Chapter 4 - S-Registers
4.1 Introduction
This chapter describes the MT2834MR6’s
S-registers
, which are small regions of memory where modem
configuration information is stored. Whereas AT commands tell a modem
what
to do, S-registers tell the
modem
how
to do it. Each S-register has a name that consists of the letter
S
and a number (
S0
,
S1
,
S2
, etc.),
hence the term
S-register
. Use the
S
r
?
command to read the value stored in an S-register, and the
S
r
=
n
command to change it.
4.2 S-Registers
S0 Number of Rings Until Modem Answers
Unit: 1 ring
Range: 0–255
Default: 1
S0 defines the number of rings the modem waits before answering an incoming call. The
default value is one ring, which causes the modem to answer the call immediately after the
first ring. The maximum number of rings that can be configured is 255. Setting the value to
zero disables autoanswer.
S1 Ring Count
Unit: 1 ring
Range: 0–255
Default: 0
S1 counts the number of rings that have occurred. It is a “read” type of register and is
seldom, if ever, used in typical operation. Each time an incoming ring signal is detected, S1
increases its value by one, up to a maximum of 255. If you set S1 to a value other than its
default value of zero, or if the value is increasing with rings, this new value remains stored
in S1 for eight seconds after the last ring is counted, after which the value reverts back to
zero.
S2 Escape Code Character
Unit: Decimal
Range: 0–127
Default: 43 (+)
S2 defines the escape code character by its decimal ASCII code. The default character is
the plus (+) sign (decimal 43). S2 may be set for any ASCII character. Setting an S2 value
greater than 127 results in no escape character, and therefore no means of entering
command mode from online mode without breaking the online connection, unless you use
the BREAK method. See Appendix H, “Multi-Tech Escape Methods.”
Note: If you change the S2 value, you must make corresponding changes in your data communications
software.