4 AT Commands, S-Registers, and Result Codes

S-Registers

Certain modem values, or parameters, are stored in memory locations called S- registers. Use the S command to read or alter the contents of S-registers (see previ- ous section).

Register

Unit

Range

Default

Description

S0

1 ring

0, 1–255

1

Sets the number of rings before the modem

 

 

 

 

answers. ATS0=0 disables autoanswer

 

 

 

 

completely.

S1

1 ring

0–255

0

Counts the rings that have occurred.

S2

decimal

0–127

43 (+)

Sets ASCII code for the escape sequence

 

 

128–255

 

character. Values greater than 127 disable

 

 

 

 

escape.

S3

decimal

0–127

13 (^M)

Sets the ASCII code for the carriage return

 

 

 

 

character.

S4

decimal

0–127

10 (^J)

Sets the ASCII code for the line feed

 

 

 

 

character.

S5

decimal

0–32

8 (^H)

Sets the ASCII code for the backspace

 

 

33–127

 

character. Values greater than 32 disable

 

 

 

 

backspace.

S6

seconds

2–255

2

Sets the time the modem waits after it goes

 

 

 

 

off-hook before it begins to dial the phone

 

 

 

 

number.

S7

seconds

1–255

50

Sets the time the modem waits for a carrier

 

 

 

 

signal before aborting a call. Also sets the

 

 

 

 

wait for silence time for the @ dial modifier,

 

 

 

 

and the time the modem waits for the dial

 

 

 

 

tone after encountering W in the dial string.

S8

seconds

0–255

2

Sets the length of the pause caused by a

 

 

 

 

comma character in a dialing command.

S9

100 ms

1–255

6

Sets the time, in tenths of a second, that the

 

 

 

 

carrier must be present before the modem

 

 

 

 

considers it valid.

S10

100 ms

1–255

14

Sets how long a carrier signal must be lost

 

 

 

 

before the modem disconnects.

S11

1 ms

50–255

95

Sets spacing and duration of dialing tones.

S12

20 ms

0–255

50

Defines the maximum period, in fiftieths of

 

 

 

 

second, allowed between receipt of the last

 

 

 

 

character of the three escape character

 

 

 

 

sequence from the computer and the send-

ing of the OK result code to the computer. (Escape code guard time).

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Multi-Tech Systems MT5600BL, MT5600BA manual Registers, Register Unit Range Default Description