Starting Communication; Using Standard Facilities - Husky MP2500 Manual

Remember that communications on the MP2500 is software controlled, so if
MP2500 fails to communicate, always check that the port is configured
correctly.

14.3 Starting communication

When you turn the MP2500 on, the serial interface is left turned off to
conserve power. When a user program attempts to send or receive data,
the MP2500 turns its interface on automatically and waits approximately 2
seconds to allow it to settle down before beginning transmission or
reception.
While the port is turning on it may send spurious characters to the remote
system, which could cause problems. To avoid this you can turn the port on
immediately before connecting to the remote system. For example, by
typing the following in MS-DOS command mode:
COPY CON COM2 E
E
T+Z E
The port remains turned on until you turn the MP2500 off, so further
transmissions are not affected in this way. If you are not going to use
communications for a while, turn off again to save battery power. (The
application may turn off the port automatically, as described in Part 3.)

14.4 Using standard facilities

The serial port can be used from standard applications, as COM2. As LPT1
is also configured as COM2, printed output will normally be routed to
COM2. Redirection can be achieved through the use of UTIL and INT
functions.
As supplied, communications can also be used in MS-DOS commands, by
using the appropriate device name in place of a filename.
The main workhorse for MS-DOS file transfer is the COPY command. For
example:
COPY COM2/A INPUT.TXT E
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