FDI2056 Use
r’s Manual
v 2.0 r 1.1
– 03/13
Copyright © 2013 Metrolab Technology SA
50
www.metrolab.com
The external trigger source (the active edge of which can be selected by software
– Please refer to chapter 4-2) must be connected to the input denoted “
External
Trigger: IN
”
of the integrator channel.
Note
: If the option
“external trigger is dispatched” is selected, the trigger signal
will be fed to all integrator channels present in the instrument. In this
particular case, the trigger must be fed to the first integrator channel
located on slot 2 only. By choosing this option, you alleviate yourself the
burden of having to wire all integrator channels with your trigger source.
See section 4-2 for more details regarding this option.
Following the reception of the
RUN
command each trigger signal defines the start
of a new integration period. The measurement sequence is terminated by the
BRK
command, after which the external trigger signals are ignored. The bit
“End
of Run
” of
STATUS
1 (bit 3) is then set.
During a measurement cycle the external trigger can be disabled by sending the
command
FPT,0
. To re-enable the external trigger the command
FPT,1
must be
executed.
Note: The
FPT
command does not terminate the measurement that is in
progress as does the
BRK
command.
A measurement sequence can be initiated by an external synchronization signal.
To select this mode, use
TRS,X,S
. This works in the manner described above,
except that the trigger signals are disabled until the first external synchronization
pulse occurs after the
RUN
command. Any following external SYNC signals are
ignored. The external synchronization shares the same pin as the ERROR signal
found on the bi-phase trigger input connector.