Multi-Tech MultiModem ISIHI-2S, Manual

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MultiModemISI Hybrid Series, ISIHI-2S 83
Chapter 4—MODEM AT Commands, S-Registers, Result Codes
Modem
Modem S-Registers
This chapter describes the ISIHI-2S’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 Sr=n command to
change it.
S-Registers
S0 Number of Rings Until Modem Answers
Unit: 1 ring
Range: 0–255
Default: 0
S0 defines the number of rings the modem waits before answering an incoming call. The
default value is zero (0), which effectively disables the auto-answer function. When auto-
answer is disabled, the modem can only answer via the ATA command. Set the S0
register value to one (1) to causes the modem to answer the call immediately after the
first ring. The maximum number of rings that can be configured is 255.
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 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: 0–255
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.
Note: If you change the S2 value, you must make corresponding changes in your data
communications software.