Campbell 21X Operator's Manual page 63

data to also
disk
and
Card
modem,
when implemented by
computer
To
the limitations of half duplex, some
links
expect
a
terminal sending
the data to the
screen.
This
saves
the
device having to echo that
Campbell Scientific device, characters are
displayed
twice (in pairs), it is likely that the
terminal is
sQt
to half duplex ralher than the
correct setting of full duplex.
IF NOTHING HAPPENS
lf
the
21X is connected via the SC32A interface
to a
terminalior computer and * is not received
after sending
carriage returns:
1.
Verify the
21X has power and that the
cables ng
the devices are securely
2.
Verify
terminal
rtions
port configured as DTE
6.5-2). The
most common
occur when
the user tries to use
a
parallel
address
,
or
doesn't know the port
(i.e. COMI or COM2). lBM,
and
most
come with a Diagnostic
the port
of
the computer or
an asynchronous serial
can
be used to identify ports,
addresses.
lf the serial port
is
equipment, then the operators
manual
give you this information.
Some
SECTION
6.
9 PlN SERIAL INPUT/OUTPUT'
configured as DTE or DCE with a
jumper
block.
Pin
functions must match with Table
6.5-1.
lf
you are using
a computer,
then a program or
communieation
software must be used to enable
the
serial port, and to make the computer
function as
a
terminal. The
port should be
enabled
for 300, 1200, or 9600 baud, 8 data
bits,
1 stop bit, and no
parity. TERM
(PC208
Software) provides this function for
IBM
PC
IXT
I
AT
IPS-2's and compatibles.
lf
you are not sure that your computer or
terminal is sending or receiving characters,
there is
a
simple way to verify
it.
Set the duplex
to
full.
Next, take
a paper clip and connect one
end
to pin 2, and the other end to pin 3
of the
serial por4. Each character typed on the
keyboard
will
be
displayed only
if
transmitted
from the
terminalon pin 2, and received on pin
3
(with half duplex.the character will be displayed
once if it is not
transmitted, or twice if it
is
transmitted).
IF
GARBAGE APPEARS
lf garbage characters appear on
the
modem/terminal, check that
the
modemlterminal's baud rate is supported by the
21X.
lf
the baud rate
is
correct, verity that the
modem/terminal is set
for
I
Data bits, and
no
Parity.
Garbage will
appear
if
7 Data bits and
no
Parity
are
used.
lf
the modem/terminal is set to
8 Data bits and even or odd Parity,
communication
cannot be established.
rial ports such as
the Super Serial
Apple computers,
can
be
6-5