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DataTalker Owner’s Manual
The MMH2834 also can detect a distant busy signal, if after dialing, it reaches a busy number.
This is useful because it allows the modem to immediately abandon a call, rather than wait 45
seconds for a carrier signal that will never come.
The MMH2834 gives you a choice between the wait-for-dial-tone (“smart”) method we just
described, and blind (“dumb”) dialing, where instead of detecting actual dial tones, the modem
relies on timed pauses. When the wait-for-dial-tone method is chosen, the busy signal detection
capability is also activated. The X command is also used to select which dialing method is used.
Five different X commands are available (X0 through X4), with five different effects on the
MMH2834’s Result Codes.
X0 Provides the basic (short) result codes and provides “dumb” dial capabilities.
X1 Provides the extended result codes and provides “dumb” dial capabilities.
The remaining X commands affect Call Progress, and turn on Extended Result Codes.
X2 Looks for dial tone only and will not provide a busy response.
X3 Looks for busy only and not look for dial tone.
X4 Looks for dial tone and for busy.
The factory default setting is X0, which selects Basic Result Codes and the blind (“dumb”)
method of dialing.