Vaisala RVP900, Руководство пользователя

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The discarded output data are not lost. The data are eventually replaced with an equal
number of zeros. Each time RVP900 discards an output word, it increments an internal 24-
bit count. When FIFO space becomes available, the processor replaces the missing data with
zero-valued placeholders.
Writing when the FIFO is full can be useful if the new command is a
RESET
which calls for
clearing the output FIFO. When the
RESET
is processed, all past and present output data
are discarded, leaving the RVP900 output section empty. This is useful when the processor
has pending output data that the user wants to discard.
8.2 No-Operation (
NOP
)
NOP is useful when a number of words must be flushed through RVP900 without side
effects.
This single-word instruction is ignored by the signal processor.
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
---------------------------------------------------------------
| | | | | | | | | | | | | | | | |
| | | 0 0 0 0 0 | Command
|------------------------------|-------|----|-------------------|
8.3 Load Range Mask (
LRMSK
)
LRMSK informs the signal processor of the ranges at which data are to be collected.
An arbitrary set of range bins are selected through an 8192- bit mask. The
N
th bit in the
mask determines whether data are acquired and processed at a range equal to:
RES x (N-1)
Table 61 LRMSK Parameters
Range Parameters Description
Range resolution Specified by a TTY setup question , in the range 25 ... 1000 meters.
Any collection of ranges may be chosen from integer multiples of that distance.
See
5.2.6 Mt<n> — Triggers for Pulsewidth n (page 116) .
Chapter 8 – Host Computer Commands
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