7.0 RS-232 COMMUNICATIONS
The Model 300 features a powerful RS-232 interface which is used both for reporting test
results and for controlling the Analyzer from a host computer. Because of the dual nature
of the RS-232 interface, the message format has been carefully designed to accommodate
both printers and host computers.
All message outputs from the Model 300 have the following format:
"X DDD:HH:MM IIII MESSAGE<CRLF>"
The "X" is a character indicating the message type (see table below).
RS-232 MESSAGE TYPES
Character Message Type
W Warning
C Control/status
D Diagnostic
T Test measurement
V Variable value
? HELP screen
TABLE 7.1
The "DDD:HH:MM" is a time-stamp indicating the day-of-year ("DDD") as a number
from 1 to 366, the hour of the day ("HH") as a number from 00 to 23, and the minute
("MM") as a number from 00 to 59.
The "IIII" is a 4-digit Analyzer I.D. number.
The "MESSAGE" field contains variable information such as warning messages, test
measurements, DAS reports, etc.
The "<CRLF>" is a carriage return-line feed combination which terminates the message
and also makes the messages appear neatly on a printer.
The uniform nature of the output messages makes it easy for a host computer to spare
them.
Input messages to the Model 300 have a format which is similar to that for output
messages:
"X COMMAND<CRLF>"
P/N 02163G1 Teledyne API Model 300 CO Analyzer Instruction Manual - Page 61