Metrohm 774, Instructions For Use Manual

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5.9 Operation via RS232 Interface
774 Oven Sample Processor, Instructions for use
103
5.9.3 Triggers
Triggers initiate an action on the 730 Sample Changer, for example, starting
a process or sending data. Triggers are marked by the introductory symbol
$.
The following triggers are possible:
$G G o Starts processes, e.g. starting the mode run or setting the RS232 interface
parameters
$S S top Stops processes
$Q Q uery Queries all information from the current node in the tree forward up to and
including the values
$Q.P P ath Queries the path from the root of the tree up to the current node
$Q.H H ighest Queries the number of son nodes of the current node
Index
$Q.N"i" N ame Queries the name of the son node with index i, i = 1...n
$D D etail-Info Queries the detailed status information
$U q U it Aborts the data flow of the instrument, for example, after $Q
The triggers $G and $S are linked to particular objects, see the summary
table page 106ff.
All other triggers can be used at any time and at all locations on the object
tree.
Examples:
Querying the value of the baud rate:
&C onfig .R SSet .B aud $Q
Querying all values of the node: RSSet: &C onfig .R SSet $Q
Querying the path of the node: RSSet: &C onfig .R SSet $Q.P
Start mode: &M ode $G
Querying the detailed status: $D
5.9.4 Status and Error Messages
In order to have an efficient control by an external control device, it must also be possible to query
status conditions. They provide information about the status of the instrument. The trigger $D initi-
ates output of the status. Status messages consist of the global status, the detailed status and
eventual error messages. The global status informs on the activity of the process, while the de-
tailed status conditions show the exact activity within the process.
The following global status conditions are possible:
$G G o The instrument is executing the last command.
$H H old The instrument has been held ($H, <HOLD> key or by an error which
effects the hold status).
$C C ontinue The instrument has been restarted actively after hold.
$R R eady The instrument has executed the last command and is ready.
$S S top A process has been aborted, e.g. by pressing the <STOP> key or
because there was an error.