Metrohm 709 IC Pump - Manual (Page 45)

5.1 RS232 interface
709 IC Pump
37
5 Interfaces
5.1 RS232 interface
5.1.1 General rules for remote control
The 709 IC Pump is equipped with the comprehensive Metrohm remote
control language, which allows full control over the instrument via an
RS232 interface, i.e. the 709 IC Pump can receive data from an external
device or send data to an external device. The 709 IC Pump sends
2 × C
R
and L
F
as the terminator of a requested data block. In contrast,
C
R
and L
F
are used as the terminator of a data line. On receipt of data
from an external device, this must always close its commands with C
R
and L
F
. If more than one command is sent on a line, ‘ ; ’ must be used
as a delimiter between the individual commands.
The data are grouped logically and readily understandable. For exam-
ple, to select the flow rate the command
&Parameter.A.Flow " 1.5 "
must be sent with entry of the boldface characters sufficing, in other
words
&Pa.A.F " 1.5 "
All quantities of the 709 IC Pump are collected in groups. The entries
for the parameters, for example, are located in the group
&Parameter
The ‘Parameter’ group contains sub-groups, e.g. for setting the pa-
rameter for the Metrohm pump head
&Parameter.A
This subgroup in turn contains the individual inquiries for the settings,
e.g. the inquiry regarding the flow rate
&Parameter.A.Flow
or regarding the setting of the minimum shutoff pressure
&Parameter.A.Pmin
The data have a hierarchical structure (tree structure). The quantities
which appear in this tree are called objects in what follows. The flow
rate is that object which is called up with the command
&Parameter.A.Flow
Once you are at the desired location in the tree, you can request the
value of the object:
&Parameter.A.Flow $Q Q for Query