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Publication No. 980938 Rev. K
Model T940 User Manual
Astronics Test Systems
Soft Front Panel Operation 5-27
The relevant VXI
plug&play
API function is:
•
tat964_setSystemClockParameters
External Offset
This control is used to specify the external System Clock offset in order to align
the clock/data relationship. The valid offset range is from 0 to 65534 (even
numbers only) and the resolution is 1/2 the MCLK period. For example if the
MCLK is set to 100 MHz then the resolution is 5 ns (1/2 of 10 ns).
The relevant VXI
plug&play
API function is:
•
tat964_setSystemClockParameters (SCLK Mode, SCLK Offset)
Synthesizer Freq (MHz)
This input control is used to specify the Frequency Synthesizer setting. The valid
frequency range is from 40 kHz to 500 MHz. Setting the control to
0
turns off the
frequency synthesizer.
The relevant VXI
plug&play
API function is:
•
tat964_setFreqSynth
Synthesizer Ref Source
This pull-down control programs the frequency synthesizer reference source.
The selections for this pull-down control are:
Table 5-24: Synthesizer Ref Source Settings
Setting
Description
Internal
Reference source set to internal 20 MHz
AUX1-AUX12
Reference source set to front panel signal
VXICLK10
Reference source set to VXI backplane 10 MHz
LCLK50
Reference source set to VXI backplane LCLK100 /
2. VXI 4.0 slot 0 and chassis are required.
The relevant VXI
plug&play
API function is:
•
tat964_setFreqSynth
Reference Freq (MHz)
This input control is used to specify the external reference frequency and only
appears when an external synthesizer reference source is selected. In these
cases, the frequency synthesizer needs to be scaled so that it can produce the
desired output frequency given the nominal external reference frequency. The
valid external reference frequency range is from 5 MHz to 80 MHz.
The relevant VXI
plug&play
API function is:
•
tat964_setFreqSynth