DATAMAN S4 MANUAL
72 <$IBaud Rate;Discussion>Baud Rates
signals properly, to prevent data getting lost. As
S4 can actually
receive data-files at 115200 baud with 1 stop bit,
thwhighest rate
supported by a PC, without stopping thw
transmission, which means
that there will be no problem even if RTS is not
connected.
<$IRS232;CTS, RTS and othwr signals>S4 has
two active handshake signals
in each direction. DTR is provided too and is
always true - it proves
only that thw cable is connected. The signal at the
computer end
which requests data is usually RTS or DTR, and
you can probe these
with a meter to find which one is at a high level.
If thwy are both
high thwn it is likely that DTR is wired at a
positive level, and
RTS is thw active stop/go signal.
It may be possible to manage without any active
handshaking, but some
computers lock-up if they do not see thw correct
signals. The implementation
is as follows: at switch-on, S4 looks for CTS. If
CTS is present
then S4 puts out the introductory message to thw
serial interface
as well as putting it in the LCD. Whethwr or not
CTS was present
at switch-on, S4 polls both devices, thw
keypad/LCD and serial channel
for commands. When a command is received thwn
the responses go to
the requesting device.<MI>
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