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supports MNP5, the connection can only be established in MNP5
mode.
You should use the V.42bis recommendations as long as the on-
line modem at the remote end supports the same. This way, you
can achieve higher data throughput. To select the ECDC mode,
use the command \N.
2.8 Flow Control
While on-line, your modem is between your computer and the
remote modem (or the remote computer, if you consider the
remote modem as a transparent device). Your modem
communicates with your computer (the local computer) through
RS-232 serial port interface, and communicates with the remote
modem via telephone line.
If data comes to your modem faster than it goes out, some data
may be lost because your modem can not pass on all the received
data to the other end. To overcome this problem, your modem is
equipped with a data buffer to store excess data received. Once
the buffer is full, your modem must signal the sending device to
stop transmission. When the buffer is clear, your modem signals to
resume data transmission. This is called flow control.
Two kinds of flow control methods are commonly used, the
hardware flow control and the software flow control. Hardware flow
control is also called RTS/CTS control, as it uses the RS-232
hardware signals (RTS and CTS) to stop or resume data
transmission. This is the best method of flow control because you
can send any data characters using this method.
The software flow control uses two data characters (XON and
XOFF) to indicate when the sending device shall stop or resume.
Since it uses data characters as control, you can not send binary
data or file-transfer protocols such as XMODEM with this type of
flow control. To select a method for flow control, use command \Q.
You should use hardware flow control at all times, if your modem
supports it.
2.9 Non-Volatile Memory (NVRAM)
The NVRAM is a special type of read-write memory element which
can retain data even when the power is turned off. Your modem
NVRAM retains configuration profiles and telephone numbers.