User manual

Publication No. 980935 Rev. M 3152B User Manual
Astronics Test Systems Operation 3-13
Using Trigger
Delay
The trigger delay value designates the time that will e
lapse from a
trigger event to the start of the waveform
at the output connector.
The trigger delay adds to the system delay time (see the definition
of System Delay in Appendix A). Therefore, when delaying
the
trigger, always consider the added factor of the system delay.
Use the following command to turn on trigger delay
and to program
the delay time value:
trig:del <value> This
command is available for
compatibility with legacy 3152A code.
A
value of 0
provides no trigger delay, and
values in the range of 10 to 2M set delays
in units of sample clock periods.
trig:del:stat 1 This
command turns on the trigger delay
function. When turned
on, the minimum
delay time is 100 ns plus system delay.
trig:de:stat 0 This
command turns off the trigger delay
function. When turned
off, the minimum
delay time is equal to the system delay.
trig:del:tim <value> This sets the delay in units of time
(an
alternative to the legacy compatible
method above which uses units of sample
clock points).
You may set the delay time
in the range of 100 ns to 20 seconds in
increments of 20 ns.
Activating the
Backplane
TTLTrg
Lines
The 3152B is
programmable to drive or receive triggers on the
VXIbus backplane trigger lines
(TTLTrg0 through TTLTrg7). It is
important to manage the trigger lines so that only one VXI
instrument drives any given line.
The signals through the TTLTrg lines are always TTL.
Use the following commands to
program the backplane trigger
lines.
outp:ttlt<n> 1 This
command defines a specific TTLTrg
line as an output. The SYNC signal is then
applied to the active TTLTrg output a
nd
the front-panel SYNC OUT connector.
The
argument
<n> designates the required
TTLTrg line,
and can take values from 0
through 7.
outp:ttlt<n> 0 This
command removes the output
definition from a specific TTLTrg line and
permits re-definition of this line
as an
input.