.TH E1432_SET_RAMP_RATE 3 E1432
.SH NAME
.nf
e1432_set_ramp_rate \- Set source ramp rate of E1432 channels
e1432_get_ramp_rate \- Get source ramp rate of E1432 channels
.fi
.IX e1432_set_ramp_rate(3) 3
.IX e1432_get_ramp_rate(3) 3
.SH SYNOPSIS
.cS
SHORTSIZ16 e1432_set_ramp_rate(E1432ID hw, SHORTSIZ16 ID,
                               FLOATSIZ32 ramp_rate)
SHORTSIZ16 e1432_get_ramp_rate(E1432ID hw, SHORTSIZ16 ID,
                               FLOATSIZ32 *ramp_rate)
.cE
.SH DESCRIPTION

\fIe1432_set_ramp_rate\fR sets the source ramp-up and ramp-down rate,
of a single channel or group of channels \fIID\fR, to the value given
in \fIramp_rate\fR.

\fIe1432_get_ramp_rate\fR returns the current value of the source ramp
rate, of a single channel or group of channels \fIID\fR, into a memory
location pointed to by \fIramp_rate\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.

\fIramp_rate\fR is the ramp-up rate.  This is the total time for the
ramp-up or ramp-down, in seconds.

For input channels, ramp rate is not generally used.

For source channels, the ramp rate is usually used to ensure that the
source signal starts and stops smoothly.  Output signals will
start at zero and then ramp up at the specified ramp_rate.  Thus, the 
first output point will be zero and succeeding values will follow the 
ramp_rate (which is applied at the clock_freq sampling rate).  NOTE:  
If the ramp_rate is set to zero, the first value output (at clock_freq 
rate) will still be zero.  This is especially noticeable at top span 
when using an Arb mode of operation since the first arb data point will 
appear to have been over-written with zero.

When a group of active source channels, within a module, is turned off
during signal generation, by a command such as \fIe1432_reset_measure\fR,
the channels ramp down together.  If the group of active source channels
spans multiple modules, the modules ramp down one at a time, in series.
This makes it take longer than expected to turn off a measurement.
If this happens when there is no signal generation, such as the off time
of a burst, there is no ramp down needed.

For tach channels, ramp rate is not generally used.
.SH "RESET VALUE"
After a reset, the \fIramp_rate\fR is set to 1 second.
.SH "RETURN VALUE"
Return 0 if successful, a (negative) error number otherwise.
.SH "SEE ALSO"
.na
e1432_get_ramp_rate_limits
.ad
