300 BPS DCM-7 Modem  (260-1394)    Registers           Faxback Doc. # 5998

Registers are used to store the parameters which control communications. 
Each register has variables that determine how the DCM-7 operates or 
supplies information on the Modem's current condition. The DCM-7 has 14 
registers:

TABLE 7. REGISTERS
REGISTERS RANGE   UNIT       FUNCTION                                 DEFAULT

 S0     0-255     Ring       Defines the rings in answer mode.           0 *3
 S1     0-255     Ring       Counts the rings.                           0
 S2     0-127     ASCII code Defines the escape code character.          43
 S3     0-127     ASCII code Defines the CR code character.              13
 S4     0-127     ASCII code Defines the LF code character.              10
 S5     0-32,127  ASCII code Defines the BS code character.              8
 S6     2-255     Seconds    Defines the dial tone wait time.            2
 S7     1-255     Seconds    Defines the carrier wait time.              30
 S8     0-255     Seconds    Defines pause duration for comma (actual    2
                             maximum value up to 255 can be input).
 S9     1-255     1/10sec.   Defines carrier detect response time.       6
 S10    1-255     1/10sec.   Defines carrier loss time to hang up.       7
 S11    50-255    Millisec.  Defines touch-tone dialing speed.           70
 S12    20-255    1/50sec.   Defines escape code guard time.             50
 S13-15                      Not Used.
 S16    0                    Self-test mode OFF.                          0
        1                    Self-test mode ON.

*3 When DIP Switch 6 is OFF, the Modem will power-up in auto answer with
S0=1.

Register S0 defines the number of ringing signals before a call is answered;
resister S1 counts the rings; registers S2-S5 define the function key
characters; registers S5-S12 control the function time and register S16 is
for the self-test.

NOTE: The ASCII code values are expressed in decimal.

COMMAND SYNTAX

You can read the current value of a register or assign a new value to match
the registers to your particular environment by using the Sx? or Sx=n com-
mand syntax.

Sx? CHECK THE REGISTER VALUE
To check the value of a register, use the Sx? syntax. The value of the
registers are displayed on the screen in decimal numbers. For example, to
check the value of register S2, type: AT S2? <ENTER>
On the screen, you will see--
        013
        OK

You can also check the values of plural registers in the same command line.
To check the values of register S3 and register S4, type: AT S3? S4? <ENTER>.
The screen might show:
        013
        010
        OK

Sx = n  CHANGE THE REGISTER VALUE
Use the Sx=n syntax to assign or change the value of a register. To assign
the value 3 to register S0, type:
AT SO=3 <ENTER>

After changing the value, the Modem signals OK. Another syntax for changing a
register value is:
AT SO <ENTER>           Set the pointer to register SO.
AT ? <ENTER>            Read the value of SO.
AT=3 <ENTER>            Assign the new value 3 to SO.

For more information on the registers, refer to Appendix B, HAYES PROTOCOL 
REFERENCE.

(css 08/05/93)