User's Manual

91
5.0 Hayes Emulation Mode
5.3.1 R EADING A ND S ETTING R EGISTERS
Use the S command to read the value of a register or to change its value.
To read the current value of a register, use the command S?, where the
number of the register is specified between the S and the ?—for example, S9?.
The decimal value of the register contents is displayed. You may read multiple
registers. For example, if you wish to read the current value in registers S0
and S7, enter the following command.
AT S0? S7?
A typical response might be 001, 030, OK, meaning the values stored in
registers S0 and S7 are 1 and 30, respectively.
To set or change a parameter, use the command S=, where the number of the
register follows S and a value between 0 and 255 (the range of values that can
be assigned to the registers) follows the equal sign:
AT S0=5
The above command changes the value stored in S0 to 5.
The S command can also be used without ? or = to point to a register that will
be read from or written to without being specified. To illustrate this, if you
enter the following command, a pointer is set to the address of register S7.
AT S7
As long as no other S command is entered, the register value can be
requested at any time without specifying the number. If you enter AT ? the
modem displays the current value in the S7 register. Similarly, if you enter
AT=8 the modem changes the value in the S7 register to 8.
5.3.2 S R EGISTER F UNCTIONS
This section describes the function of each S register. Table 5-3 lists the range
of possible parameters and the default value for each S register.
• S0 — Ring To Answer On. The value in this register determines on what
ring (first, second, third, etc.) the modem answers. Setting S0 to 0
disables auto-answer.
• S1 — Ring Count. Register S1 counts the number of ring signals for each
incoming call. If more than 8 seconds pass since the last ring, S1 is cleared
to zero.
• S2 — Escape-Code Character. The escape code is effective for
asynchronous operation only. Values greater than 127-completely disable
escape code detection and prevent you from issuing a hang-up command.