.TH E1432_SET_OVERLAP 3 E1432
.SH NAME
.nf
e1432_set_overlap \- Set measurement overlap
e1432_get_overlap \- Get current measurement overlap
.fi
.IX e1432_set_overlap(3) 3
.IX e1432_get_overlap(3) 3
.SH SYNOPSIS
.cS
SHORTSIZ16 e1432_set_overlap(E1432ID hw, SHORTSIZ16 ID,
                             LONGSIZ32 overlap)
SHORTSIZ16 e1432_get_overlap(E1432ID hw, SHORTSIZ16 ID,
                             LONGSIZ32 *overlap)
.cE
.SH DESCRIPTION
\fIe1432_set_overlap\fR sets the measurement overlap, of a single
channel or group of channels \fIID\fR, to the value given in
\fIoverlap\fR.

\fIe1432_get_overlap\fR returns the current value of the measurement
overlap, of a single channel or group of channels \fIID\fR, into a
memory location pointed to by \fIoverlap\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.

\fIoverlap\fR selects the number of data points that can overlap
between one block and the next.  The value may be positive or
negative.  A negative value for the \fIoverlap\fR means that there is
a separation between successive blocks.  When the data size is set to
\fBE1432_DATA_SIZE_16\fR, then the overlap will be rounded down to an
even number.  When the in order tracking mode the number of point of overlap
are specified in terms of resampled time points.

When the data mode is set to \fBE1432_BLOCK_MODE\fR, then the
\fIoverlap\fR is not used.  This is like the block mode of the E1431
and of the HP35652 and HP35655.

When the data mode is set to \fBE1432_CONTINUOUS_MODE\fR, then the
\fIoverlap\fR specifies the number of samples that overlap between
successive data blocks.  The maximum legal value is one less than the
blocksize, while the minimum legal value is some large negative
number.  A negative overlap corresponds to a gap between one block and
the next.

When the data mode is set to \fBE1432_DATA_MODE_OVERLAP_BLOCK\fR, the
\fIoverlap\fR specifies the point at which the module starts looking
for a trigger for the next block of data.  A positive value means that
the trigger can happen before the end of the previous block.  A
negative value causes a gap after the previous block before a trigger
can occur.  Note that this just determines when the E1432 module
reaches the \fBTRIGGER\fR state.  Unlike in continuous mode, a trigger must
still occur before a new data block is collected.
.SH "RESET VALUE"
After a reset, the \fIoverlap\fR is set to \fB0\fR.
.SH "RETURN VALUE"
Return 0 if successful, a (negative) error number otherwise.
.SH "SEE ALSO"
.na
e1432_set_blocksize, e1432_set_data_mode, e1432_get_overlap_limits
.ad
