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Chapter 4 - AT Commands, S-Registers, and Result Codes
S75 Maximum V.110 Buffer Size
S76 V.110 Network rate
S77 V.110 Network Rate Control
S80 Persistent DTR Dialing Delay
Note: V.110 is supported in build MTA128ST-USB only.
S-Register: S0
Function: Number of Rings Until Answer
Unit: 1 ring
Range: 0255
Default: 1
Description:Sets the number of rings the TA waits for before it answers and begins its
connect sequence. S0=0 turns off the ability to automatically answer a call.
S0=1 causes the TA to automatically answer after 1 ring. If the S0 value is
set too high, the calling device may time out before the TA answers the call.
For autoanswer, S0 must have a nonzero value, DTR must be high (&D
command), and the TA must be offline.
S-Register: S1
Function: Ring Count
Unit: 1 ring
Range: 0255
Default: 0
Description:Counts the number of rings that have occurred, up to a maximum of 255. It is
a read-only register and is seldom used in typical operation. 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 time the value reverts to zero.
S-Register: S2
Function: Escape Character
Unit: Decimal ASCII code
Range: 0127
Default: 43 (+)
Description:Specifies the character used by the TA to escape from data mode and return
to command mode.
S-Register: S3
Function: Carriage Return Character
Unit: Decimal ASCII code
Range: 0127
Default: 13 (^M)
Description:Specifies the character used by the TA to indicate the end of a command
line.
S-Register: S4
Function: Line Feed Character
Unit: Decimal ASCII code
Range: 0127
Default: 10 (^J)
Description:Specifies the character used by the TA to indicate the end of a status
message.