Envoy ACP/XF Application Programming Manual

EnvoyACP/XF and the Application Task
EnvoyACP/XF Application Programming Manual–132179
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Automatic Calling for V.25 bis Modems
Automatic Calling for V.25 bis Modems
This section describes how EnvoyACP/XF supports automatic calling for V.25 bis
modems. If you do not require this function, you may skip this section.
V.25 bis is a CCITT protocol recommendation for serial modems that have automatic
calling capability. The hardware configuration and the software environment for V.25 bis
support is illustrated in Figure 1-2
.
V.25 Modifier
The V.25 modifier affects your system in the following ways:
•
It indicates to the EnvoyACP/XF interface that a V.25 bis modem is configured for
the line.
•
It implies that the EnvoyACP/XF line is switched.
•
It works only with properly configured V.25 bis modems. (See the EnvoyACP/XF
Configuration Manual for information about how to configure V.25 bis modems.)
V.25 bis Restrictions
EnvoyACP/XF supports only bit-synchronous protocols. EnvoyACP/XF works only with
V.25 bis-compatible automatic calling modems; EnvoyACP/XF does not work with
asynchronous or byte-synchronous protocols.
V.25 bis Features
V.25 bis with EnvoyACP/XF features are described below:
•
V.25 bis modem acts as the data circuit-terminating equipment (DCE).
•
The application uses the standard broadcast address Hex FF to address the DCE in
V.25 bis mode.
Figure 1-2. EnvoyACP/XF for V.25 bis Hardware and Software
ServerNet WAN
Concentrator
Telephone
Line
V.25 bis
Modem
Bit-Synchronous Line
Application
EnvoyACP/XF
Line Handler
023