182
Configuring External Input/Output (I/O) Terminals
Simultaneously starting measurement using external triggers
This section describes how to synchronize the measurement start time for multiple instruments
using trigger input and trigger output.
Since each instrument generates its own sampling clock, data acquisition times will diverge if
measurement is continued for an extended period of time.
There are two methods for synchronizing measurement start times: daisy chain operation and
parallel synchronized operation.
Daisy chain operation
When a trigger activates for any instrument, triggers will also activate for other instruments.
When a large number of instruments are connected, divergence among individual devices’ trigger
times will increase.
Connection method
Connect one instrument’s trigger output (I/O 4) to the next
instrument’s trigger input (I/O 3).
Repeat this connection until all the instruments have been
connected.
Configuration method
• Set
[Trigger]
to
[ON]
for all the instruments. (p. 84)
• Set
[External trigger]
to
[ON]
for all the instruments. (p. 94)
• Set
[External input 3]
to
[Trigger input]
and the edge to
[↓]
for all the instruments. (p. 179)
• Set
[External output]
to
[Trigger output]
for all the
Example connections
EXT.TRIG
TRIG OUT
GND
EXT.TRIG
TRIG OUT
GND
EXT.TRIG
TRIG OUT
GND
GND
Parallel synchronized operation
Use one instrument as the master (trigger monitoring) and the rest as subordinates.
When a trigger activates for the master instrument, triggers will also activate for the subordinate
instruments.
Divergence in trigger times can be minimized using this method, even when the number of
connected instruments increases.
Connection method
Connect the master instrument's trigger output (I/O 4) to all
subordinate instruments’ trigger input (I/O 3).
Configuration method
• Set
[Trigger]
to
[ON]
for all the instruments. (p. 84)
• Set
[External trigger]
to
[ON]
for all the subordinate
• Set
[External input 3]
to
[Trigger input]
and the edge to
[↓]
for all the subordinate instruments. (p. 179)
• Set
[External output]
to
[Trigger output]
for the master
Example connections
EXT.TRIG
TRIG OUT
GND
EXT.TRIG
TRIG OUT
GND
EXT.TRIG
TRIG OUT
GND
GND
Master
Subordinate
Subordinate
Summary of Contents for LR8450
Page 68: ...64 Observing Waveforms Alarm...
Page 72: ...68 Observing Waveforms 3 Numerical calculation Numerical calculation results...
Page 131: ...128 Acquiring Data with a Computer PC...
Page 175: ...172 Controlling the System...
Page 233: ...230 Controlling the Instrument with Communication Commands...
Page 271: ...268 Plug in Module Specifications...
