Metrohm 774 - Page 86

5 Detailed description
774 Oven Sample Processor, Instructions for use
80
Setting special bit patterns allows flexible control of connected instruments.
Here the following is valid: 0 = line inactive
1 = line active
* = arbitrary line state
Example: 00000001 = input 0 is active = instrument 1 "Ready"
The bit pattern (= line state ) can be taken over interactively with the LEARN
function. See page 34.
Details about the remote interface are found on page 97.
1
SCAN
>sample sequence
8 SCN:RS
Rm,RS
Clear value: ∗R"
14 ASCII characters
Scanning the RS232 interface
= scan for "Ready" status message
arbitrary series of 14 characters
In a sequence the SCN:RS command causes method processing to stop
until the predefined character string (up to 14 characters) is received via se-
rial RS 232 interface. The received data is compared character by charac-
ter.
Be sure that the interface parameters agree with those of the instrument
connected (see Configuration Menu '>RS232 settings', page 66).
Any letters, numbers and special characters from the character set of the
sample changer can be chosen.
The asterisk (*) may be used as a wildcard for an arbitrary character or
character string. (If '*' is to be interpreted as an ASCII character, '**' has to
be set.) A wildcard may be used in any position of a character string. If the
first part of character string is correctly identified, the first appearance of the
character following the asterisk (*) is scanned. When it is found, the next
part of the character string is compared.
This function is especially suited to instruments with Metrohm remote con-
trol language. Here the Auto-Info status messages can be scanned. The
most useful of these are:
*.T.R" Ready, 'ready' state attained, for ex., after titration
*.T.F" Final, end of the determination is reached
*.T.S" Stop, instrument manually halted
*.T.G" Go, instrument was started
*.E;* Error, error message
'*' can be set as a wildcard for a particular character string. Example: *R"
instead of !".T.R" (status message 'ready' after completing a titration).
These status messages however, are only transmitted if the corresponding
status message has been previously switched on, for example, in the the
start sequence with the command:
CTL:RS &Se.A.T.R"ON", for example.
CTL command, see below.
With the LEARN function transmitted data (=character strings) can be
taken over interactively. See page 34.