User manual

Table Of Contents
Publication No. 980935 Rev. M 3152B User Manual
Astronics Test Systems Operation 3-37
valid trigger signal, and ends after the gate has closed. Processing
time for the reading and the display is roughly 100 ms
. In this mode,
the counter can take a maximum of ten readings per second.
2. Gate time period must be higher than the signal period
The gate must open for an interval that allows
enough transitions to
pass through the counter gate. If the gate time is too short to
measure a signal, the gate will open,
but no results can be
obtained.
3. Auxiliary functions disable waveform generation
When the Counter/Timer mode is selected, all operat
ions of the
waveform generator
are stopped, and the waveform memory is
purged.
Synchronizing
through the Local
Bus
Use the following commands to set up and control synchronization
(phase locking) of two modules through the Local Bus:
inst:coup:path lbus
This sets the coupling (synchronization)
path to the Local Bus (LBUS). This
command must be sent to the master
module and the slave module(s).
inst:coup:mode mast Send this command to the 3152B that
will
be
the master module to which other
modules will be phase-locked.
inst:coup:mode slav Send this command to the
slave
module(s) that will be phase locked to the
master module.
inst:coup:stat on Send this command to the master
module,
and then to the
slave module. It enables
coupling (phase locking).
Example:
The following procedure sets up a 3152B module as the master,
sets up another 3152B module as the slave,
and monitors the
outputs of both modules to observe that they are phase locked.
1. Install Local Bus jumpers on both 3152B modules
(refer to
Chapter 2, in the Local Bus Configuration section).
2. Install the two modules in
to adjacent slots in a VXI chassis. The
3152B on the left will be the master, and the 3152B on the right
will be the slave.
3. Turn on power to the VXI chassis.
4. Connect the output connector of
the left module (master) to
channel 1 of the oscilloscope.