.TH E1432_SET_SOURCE_SEED 3 E1432
.SH NAME
.nf
e1432_set_source_seed \- Set seed for source random modes
e1432_get_source_seed \- Get seed for source random modes
.fi
.IX e1432_set_source_seed(3) 3
.IX e1432_get_source_seed(3) 3
.SH SYNOPSIS
.cS
SHORTSIZ16 e1432_set_source_seed(E1432ID hw, SHORTSIZ16 ID,
                                 SHORTSIZ16 source_seed)
SHORTSIZ16 e1432_get_source_seed(E1432ID hw, SHORTSIZ16 ID,
                                 SHORTSIZ16 *source_seed)
.cE
.SH DESCRIPTION

\fIe1432_set_source_seed\fR sets the seed used by the source random
modes, of a single channel or group of channels \fIID\fR, to the value
given in \fIsource_seed\fR.  This value is used when the source is in
\fBE1432_SOURCE_MODE_RAND\fR or \fBE1432_SOURCE_MODE_BRAND\fR modes.

\fIe1432_get_source_seed\fR returns the current value of the source
randomization seed, of a single channel or group of channels \fIID\fR,
into a memory location pointed to by \fIsource_seed\fR.

\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.

\fIsource_seed\fR is the seed value.  Only the bottom eight bits of
this seed value are currently used.  However, each of the 256 possible
seeds results in uncorrelated signals (i.e. a source channel with a
seed of 0 and a source channel with a seed of 1 will produce random
noise that is uncorrelated with each other).

For input channels, the source seed is not used.

For source channels, the source seed is used when in
\fBE1432_SOURCE_MODE_RAND\fR or \fBE1432_SOURCE_MODE_BRAND\fR modes.

For tach channels, the source seed is not used.

\fBNote:\fR The reset value for this parameter is the same for all
source channels.  This means that unless the application sets the
source seeds, all source channels will produces the same random data.
Furthermore, unless the seed is changed between successive
measurements, each source will produce the same data stream from
measurement to measurement.
.SH "RESET VALUE"
After a reset, the \fIsource_seed\fR is set to 3.
.SH "RETURN VALUE"
Return 0 if successful, a (negative) error number otherwise.
.SH "SEE ALSO"
.na
e1432_set_source_mode, e1432_get_source_seed_limits
.ad
