Chapter 2
NI 5450 Overview
NI PXIe-5450 User Manual
2-6
ni.com
The Reference clock uses the internal clock by default. Call the niFgen
Configure Reference Clock VI or the
niFgen_ConfigureReferenceClock
function to configure the
Reference clock source.
When configuring an external Reference clock, you must configure the
external Reference clock frequency if it is different from the 10 MHz
default setting. Set the Reference clock frequency with the niFgen
Configure Reference Clock VI or the
niFgen_ConfigureReferenceClock
function.
Note
You also can phase-lock the signal generator to other NI devices using the common
PXI 10 MHz backplane clock on PXI devices.
External Sample Clock Input
In addition to phase-locking, the CLK IN connector also can receive an
external Sample clock. Refer to the device specifications for the allowable
external Sample clock frequencies and signal characteristics.
Tip
When configuring an external Sample clock, set the sample rate to the exact
frequency you are using to avoid data errors. Set the sample rate by calling the niFgen Set
Sample Rate VI or
niFgen_ConfigureSampleRate
function.
Configure the Sample clock source with niFgen Configure Sample Clock
Source VI or the
niFgen_ConfigureSampleClockSource
function.
The Sample clock uses the internal clock by default.
External Sample Clock Timebase Input
The CLK IN connector also can receive an external Sample clock timebase.
Refer to the device specifications for the allowable external Sample clock
timebase frequencies and signal characteristics.
Configure the Sample clock timebase source with the Sample Clock
Timebase Source and Sample Clock Timebase Rate properties or the
NIFGEN_ATTR_SAMPLE_CLOCK_TIMEBASE_SOURCE
and
NIFGEN_ATTR_SAMPLE_CLOCK_TIMEBASE_RATE
attributes. The device
uses the internal sample clock timebase by default.
