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C H A P T E R 2 5
Modem Setup Service
25-4
About the Modem Setup Service
4. The modem endpoint is reconfigured with pass-through mode disabled, and
control is returned to the client application, which can proceed with its
Bind
and
Connect
calls.
"Defining a Modem Setup" (page 25-5) describes how to define a modem setup.
Modem Communication Tool Requirements
25
The Newton modem communication tool expects certain characteristics from a
modem. These characteristics are described here.
The modem tool expects a PCMCIA modem to use a 16450 or 16550 UART chip.
The modem tool expects hardware flow control in both serial and PCMCIA
modems. In modems not supporting hardware flow control, direct connect
support is required, and the modem profile constant
kDirectConnectOnly
must be set to
true
. This means that the modem tool and the modem must be
running at the same bit rate, allowing for no compression or error correction
protocols to be used by the modem. (When operating in direct connect mode,
the data rate of the modem tool is automatically adjusted to the data rate stated
in the "CONNECT SEXTETS" message.)
The modem tool expects control signals to be used as follows:
The modem tool uses RTS to control data flow from the modem.
The modem uses CTS to control data flow from the modem tool.
Support of the DCD signal is optional. In general, the modem tool expects
DCD to reflect the actual carrier state. The usage of this signal by the modem
tool is governed by the
kUseHardwareCD
constant.
The modem tool expects non-verbose textual responses from the modem.
The modem tool expects no echo.
The modem tool currently supports the Class 1 protocol for FAX connections;
under some circumstance (see the note below), the modem tool supports the
Class 2 protocol. The configuration string defined by the constant
kConfigStrNoEC
is used for sending and receiving FAX documents.
Additionally, these other requirements apply to the FAX service:
Flow control is required. In modems not supporting hardware flow control
(where
kDirectConnectOnly
=
true
), XON/XOFF software flow
control must be enabled.
Buffering must be enabled.
The
kConfigSpeed
constant must be set to higher than the highest connect
rate of which the modem is capable. For example, if the modem supports
14400, set
kConfigSpeed
to 19200; if the modem supports 28800, set
kConfigSpeed
to 54600.
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