Agilent Technologies E1437A, Руководство пользователя

Страница: 133 / 214

Description:
CLOCK:SETUP is used to configure all timing parameters used for sampling (ADC
clock) and decimation/zoom (DSP clock). This command, as well as the other
CLOCK commands covered in this description, is used to select the source and
distribution of clocking and synchronization signals used by the E1437 module. The
primary clock signal used by th e module is th e ADC clock, for wh ich th e rising edges
indicate the time for each sample of the analog-to-digital converter. Another clock
signal is the DSP clock, which drives the digital signal processing and memory
sections of the module. Normally the DSP clock is the same as the ADC clock, and
data is transferred synchronously from the ADC to the DSP portion of the module.
However, in certain situations the two clocks may be independent, requiring
asynchronous data transfers from the ADC to the DSP. The remaining CLOCK
commands and queries listed above set or query the parameters individually.
Parameter definitions:
is used to specify whether the module uses a shared ADC clock and
SYNC signal. Modules in multi-module systems must all have the same sync
parameter setting.
parameter
value
multisync parameter definition
0 OFF. The ADC clock and SYNC are generated locally
1
FRONT. The module uses the shared clock and SYNC provided on the front panel
distribution connectors
2
REAR. The module uses the shared ADC clock and SYNC signals which are distributed on
the VXI backplane using the ECL trigger lines
selects the clock source that is used to drive the analog to digital converter
(ADC) for single module operation or when a module is used as the master ADC
clock source for a multi-module system. In multi-module systems the source
parameter is ignored for all but the master module.
parameter
value
source parameter definition
0 20.48 MHz internal oscillator
1 20 MHz internal oscillator
2 EXT. TTL, ECL, or sine signal on the external, BNC, front panel clock input connector
3
EXT:PLL. Takes a 10 MHz reference from another instrument on the external, BNC, front
panel clock input connector and uses a PLL to convert it to a 20 MHz reference
E1437A CLOCK:SETUP
ASCII Overview and Commands command/query
5-10
Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.com