.TH E1432_GET_SCALE 3 E1432
.SH NAME
e1432_get_scale \- Calculate scale factor for current board settings
.IX e1432_get_scale(3) 3
.SH SYNOPSIS
.cS
SHORTSIZ16 e1432_get_scale(E1432ID hw, SHORTSIZ16 ID, FLOATSIZ64 *scale)
.cE
.SH DESCRIPTION
\fBThis function is not needed by most users.\fR The typical
application uses \fIe1432_read_float32_data\fR or
\fIe1432_read_float64_data\fR to get input data from the E143x
modules, and those functions already scale their results correctly to
volts or picoCoulombs.  In fact, those functions internally call
\fIe1432_get_scale\fR to get the correct scale factor to use.

\fIe1432_get_scale\fR returns a scaling factor to convert raw input
data into volts.  The data from \fIe1432_read_raw_data\fR should be
multiplied by this scale factor to get voltage (or picoCoulombs if the
input channel is in charge mode).  The scale factor accounts for
break-out box settings, range, span, and multi-pass filtering effects.
A call with group ID will return \fBERR1432_PARAMETER_UNEQUAL\fR if
all channels do not have the same scale factor.  \fBNOTE: the scale
factor can only by applied to raw time data .... frequency and order
data are already scaled to volts internally.\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 the ID of a group or single channel.

It is possible to set up an input channel to monitor the tach signal
seen on a tach channel input.  Normally, when this is done the tach
channel drives CALOUT, the substrate connects CALOUT to CALIN, and the
input channel monitors CALIN.  (See \fIe1432_set_input_high\fR and
\fIe1432_set_calin\fR for details.)  The scale factor from
\fIe1432_get_scale\fR will correctly account for the tach board and
calibration scale factors.

It is also possible to set up a tach channel to drive the VXI sumbus,
and have the sumbus drive CALIN, and have an input channel monitor
CALIN.  For this to work correctly, pass \fBE1432_CALIN_SUMBUS_TACH\fR
(not \fBE1432_CALIN_SUMBUS\fR) to \fIe1432_set_calin\fR, to ensure
that the input channel can figure out the correct scale factor.

.SH "RESET VALUE"
Not applicable.
.SH "RETURN VALUE"
Return 0 if successful, a (negative) error number otherwise.
.SH "SEE ALSO"
.na
e1432_read_float32_data, e1432_read_float64_data, e1432_read_raw_data,
e1432_set_data_size, e1432_set_input_high
.ad
