OXITEST PLUS 7 OPERATING MANUAL
Figure 5 - Connector Pin-outs
4.2
Mechanical Interface
The
Oxitest Plus 7
RS-232 port located on the right side of the unit is a 5-pin mini-DIN female
connector. The R-103 DB9 RS-232 accessory cable (P/N 7100-248) is available to connect to the 5-
pin mini-DIN female connector.
A cable made to the specifications in the table following may be used to connect
Oxitest Plus 7
to
the COM port of a PC or medTester.
Oxitest Plus 7
mates with the 5-pin miniDIN male
connector, and the PC or medTester mates with the DB-9 female connector.
(Oxitest)
5-pin miniDIN
(medTester/PC)
DB-25 female
DB-9 female
pin 5 (TXD)
pin 2,3 (RXD)
pin 1 (CTS)
pin 4 (BUSY)
shield (GND)
to
to
to
to
to
pin 3 (RXD)
pin 2 (TXD)
pin 4 (RTS)
pin 20 (DTR)
pin 7 (GND)
pin 2 (RXD)
pin 3 (TXD)
pin 7 (RTS)
pin 4 (DTR)
pin 5 (GND)
4.3
Functional Description
Oxitest Plus 7
RS-232 commands are ASCII strings consisting of two to four upper case letters
followed by zero to three numeric digits. Command strings are terminated with the carriage return
character (ØD hex), or by carriage return followed by the line feed character (ØA hex).
The
Oxitest Plus 7
has a bidirectional RS-232 port and monitors the RTS and DTR lines when
handshaking with external serial printers. Control programs should ensure that COM port RTS and
DTR lines are set high and that at least 100 msec is allowed between transmissions to accommodate
command execution time. A delay of less than 100 msec between transmissions may produce
unexpected results.
If
Oxitest Plus 7
receives a valid RS-232 command,
Oxitest Plus 7
will execute the command,
update the LCD to reflect the change and transmit the “*” character via its RS-232 port. If
Oxitest Plus 7
receives an invalid or erroneous command, the command will not be executed, the
Oxitest Plus 7
will transmit the “?” character via its RS-232 port.
Computer Control/Chapter 4
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