.TH E1432_SET_TTLTRG_TRIGGER 3 E1432
.SH NAME
.nf
e1432_set_ttltrg_trigger \- Select a TTLTRG line for once-per-loop trigger
e1432_get_ttltrg_trigger \- Get current TTLTRG line for once-per-loop trigger
.fi
.IX e1432_set_ttltrg_trigger(3) 3
.IX e1432_get_ttltrg_trigger(3) 3
.SH SYNOPSIS
.cS
SHORTSIZ16 e1432_set_ttltrg_trigger(E1432ID hw, SHORTSIZ16 ID,
                                   SHORTSIZ16 ttltrg)
SHORTSIZ16 e1432_get_ttltrg_trigger(E1432ID hw, SHORTSIZ16 ID,
                                   SHORTSIZ16 *ttltrg)
.cE
.SH DESCRIPTION

The one-pulse-per-loop trigger is not normally used by the E1432
module, so this function is not normally used.

\fIe1432_set_ttltrg_trigger\fR sets the VXI TTLTRG line used for a
one-pulse-per-loop trigger.  If a measurement is in progress while
calling this function, the measurement is aborted.  The
one-pulse-per-loop trigger is asserted at the start of each block of
data acquired from an E1432.  It is not asserted to synchronise the
modules at the start of a measurement, nor does it get asserted before
the arm state as the sync/arm/trigger line does.  This line is
therefore not compatible with the E1431 8-channel input module.

\fIe1432_get_ttltrg_trigger\fR returns the currently selected VXI
TTLTRG line for the one-pulse-per-loop trigger in the memory location
pointed to by \fIttltrg\fR.

This parameter is a "global" parameter.  It applies to an entire E1432
module rather than to one of its channels.  The \fIID\fR parameter is
used only to identify which module the function applies to, and all
channels in that module will report the same value for this parameter.

\fIhw\fR must be the result of a successful call to
\fIe1432_assign_channel_numbers\fR, and specifies the group of
hardware to talk to.

\fIID\fR is either the ID of a group of channels that was obtained with a
call to \fIe1432_create_channel_group\fR, or the ID of a single channel.

\fIttltrg\fR selects a VXI ttltrg line to be used for the
one-pulse-per-loop trigger.

\fBE1432_TTLTRG_0\fR selects TTLTRG0 for the trigger.
\fBE1432_TTLTRG_1\fR selects TTLTRG1 for the trigger.
\fBE1432_TTLTRG_2\fR selects TTLTRG2 for the trigger.
\fBE1432_TTLTRG_3\fR selects TTLTRG3 for the trigger.
\fBE1432_TTLTRG_4\fR selects TTLTRG4 for the trigger.
\fBE1432_TTLTRG_5\fR selects TTLTRG5 for the trigger.
\fBE1432_TTLTRG_6\fR selects TTLTRG6 for the trigger.
\fBE1432_TTLTRG_7\fR selects TTLTRG7 for the trigger.

The mere selection of the TTLTRG line by this function does not
necessarily cause the trigger to get driven onto that TTLTRG line.
The TTLTRG line is driven only if one of the following conditions is
met:

1. \fIe1432_set_multi_sync\fR is \fBE1432_SYSTEM_SYNC_VXD\fR or
   \fBE1432_SYSTEM_SYNC_VXD_MIN\fR.

2. \fIe1432_set_clock_source\fR is \fBE1432_CLOCK_SOURCE_VXI\fR
   or \fBE1432_CLOCK_VXI_DEC_3\fR.
.SH "RESET VALUE"
After a reset, \fIttltrg\fR is set to \fBE1432_TTLTRG_0\fR.
.SH "RETURN VALUE"
Return 0 if successful, a (negative) error number otherwise.
.SH "SEE ALSO"
.na
e1432_set_ttltrg_clock, e1432_set_ttltrg_satrg,
e1432_set_ttltrg_gclock, e1432_set_ttltrg_lines
.ad
