Coastcom D/I Mux III System, User Manual

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D/I Mux III User’s Manual Appendix G. Modem Interfaces
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Table H-2. Hayes Smartmodem 300 Command Set (Continued)
Command Description
H0
H1
H2
Go on hook (hang up).
Line and auxiliary relays off hook.
Line relay only off hook.
The Hayes Smartmodem contains an additional relay that can be used to control
equipment, independent of the telephone line relay.
O0 Go to on-line state.
This command returns the modem on-line, and is primarily for issue after going off-line with
the
escape sequence +++ .
M0
M1
M2
Speaker off.
Speaker on until carrier is detected.
Speaker always on.
The modem loudspeaker is often the primary indicator of the progress of a call, from dialing
to establishing a connection. For this reason, the default setting is
speaker on until carrier
is detected. However, the speaker can be left on for troubleshooting, or turned off
completely as desired. This command
does not permit speaker volume control. Some
Hayes-compatible modems provide an external speaker volume knob for this. In the later
1200 model, Hayes implemented basic software control of the speaker volume with the
L
command.
Q0
Q1
Modem returns result codes.
Modem does not return result codes.
Normally, software depends on the modem to return command result codes, so Q0 must
be set.
This Hayes command set option is provided for those rare occasions when echo must be
off.
Sr
Sr=n
Sr?
Set pointer to address of register "r".
Set register "r" to value "n".
Display value stored in register "r".
To assign a value to one of the Smartmodem's S-registers (e.g., to increase dialing speed
to its maximum) issue the command
ATS11=50 . To read the new value in S11, issue the
command ATS11? . Many registers have ranges of acceptable values. However, the
modem does not ignore invalid assignments and instead, can set the modem to an invalid
value. Hayes-compatible modems respond in various ways to invalid values.
Hayes S-register definitions follow this command listing.
V0
V1
Display result codes in numeric form.
Display result codes in verbose form (as words).
Numeric codes are easier for software to interpret, whereas word responses are easier for
people to interpret. Word responses are also less susceptible to software misinterpretation
due to line noise.
Z
Reset modem, and recall factory configuration.
On the Smartmodem 300, this is equivalent to turning the modem off and back on. On
later modems, EPROMs and command set extensions can store a default configuration
different from that set at the factory, and the effect of this command varies across products.