Teledyne GFC-7000T - Trace CO2 Analyzer - manual - Manual (Page 166)

Operating Instructions Model GFC7000TA Carbon Dioxide Analyzer
Teledyne Analytical Instruments 148
followed by zero or more digits, an optional decimal point, and zero or more digits. (At least one digit
must appear before or after the decimal point.) Scientific notation is not permitted. For example, +1.0,
1234.5678
, -0.1, 1 are all valid floating-point numbers.
 Boolean expressions are used to specify the value of variables or I/O signals that may assume only
two values. They are denoted by the keywords ON and OFF.
 Text strings are used to represent data that cannot be easily represented by other data types, such
as data channel names, which may contain letters and numbers. They consist of a quotation mark,
followed by one or more printable characters, including spaces, letters, numbers, and symbols, and a
final quotation mark. For example, “a”, “1”, “123abc”, and “()[]<>” are all valid text strings. It is not
possible to include a quotation mark character within a text string.
 Some commands allow you to access variables, messages, and other items, such as DAS data
channels, by name. When using these commands, you must type the entire name of the item; you
cannot abbreviate any names.
6.15.2.5. Status Reporting
Reporting of status messages as an audit trail is one of the three principal uses for the RS-232 interface
(the other two being the command line interface for controlling the instrument and the download of data in
electronic format). You can effectively disable the reporting feature by setting the interface to quiet mode
(Section 6.11.5., Table 6-10).
Status reports include DAS data (when reporting is enabled), warning messages, calibration and
diagnostic status messages. Refer to Appendix A-3 for a list of the possible messages, and this for
information on controlling the instrument through the RS-232 interface.
General Message Format
All messages from the instrument (including those in response to a command line request) are in the
format:
X DDD:HH:MM [Id] MESSAGE<CRLF>
Where:
X is a command type designator, a single character indicating the message type,
as shown in the Table 6-27.
DDD:HH:MM is the time stamp, the date and time when the message was issued. It consists of
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.
[ID] is the analyzer ID, a number with 1 to 4 digits.
MESSAGE is the message content that may contain warning messages, test
measurements, DAS reports, variable values, etc.
<CRLF> is a carriage return / line feed pair, which terminates the message.
The uniform nature of the output messages makes it easy for a host computer to parse them into an easy
structure. Keep in mind that the front panel display does not give any information on the time a message
was issued, hence it is useful to log such messages for trouble-shooting and reference purposes.