Campbell CR7, Инструкция по эксплуатации

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SECTION 6. 9 PIN SERIAL INPUT/OUTPUT
6-5
terminal is set to half duplex rather than the
correct setting of full duplex.
IF NOTHING HAPPENS
If the CR7 is connected via the SC32A interface
to a terminal or computer and * is not received
after sending carriage returns:
1. Verify that the CR7 has power and that the
cables connecting the devices are securely
connected.
2. Verify that the port of the computer or
terminal is an asynchronous serial
communications port configured as DTE
(see Table 6.5-1). The most common
problems occur when the user tries to use a
parallel port, or doesn't know the port
address (i.e. COM1 or COM2). IBM, and
most compatibles come with a Diagnostic
disk which can be used to identify ports,
and their addresses. If the serial port is
standard equipment, then the operators
manual should give you this information.
Some serial ports such as the Super Serial
Card for Apple computers, can be
configured as DTE or DCE with a jumper
block. Pin functions must match with Table
6.5-1.
If you are using a computer without the PC208
software, then a program or communication
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.
If 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 port. Each character typed on the
keyboard will be displayed only if transmitted
from the terminal on 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
If garbage characters appear on the
modem/terminal, check that the
modem/terminal's baud rate is supported by the
CR7. If the baud rate is correct, verify that the
modem/terminal is set for 8 Data bits, and no
Parity. Garbage will appear if 7 Data bits and
no Parity are used. If the modem/terminal is set
to 8 Data bits and even or odd Parity,
communication cannot be established.