Vaisala RVP900, Руководство пользователя

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Command Example
Write
(
WRIT )
Example:
WRIT|<data>
, where
<data>
is some binary data.
This data is written to RVP900. The data size should be even.
Read Status
(
STAT
)
Example: STAT| reads the status bits back from the RVP900. This is a 1 bit value,
set to 1 if the RVP900 has data available in its output buffer.
It returns
Ack|0 , Ack|1 , or Nak .
This is equivalent to the dspr_status() call in the dsp library.
Set Information
(
INFO )
Example: INFO|
ByteOrder=LittleEndian,WillCompress=1,Version=7.32 .
This command can be used to inform RVP902
DspExport
about the host
computer. Available options are:
• ByteOrder —Informs DspExport of the byte order of the host computer.
This is needed because all the data read or written to/from the RVP900 is in
16-bit words. If the host computer has a different byte order from the RVP900,
DspExport byte swaps the data.
•
WillCompress
—Informs
DspExport
to use compression or not.
Compression is only used if both sides agree to use it. The host computer
should only set this to 1 if it received a
CanCompress
of 1 on initial connection.
The data from normal
READ
commands is compressed.
If the data is compressed, it replies with the acknowledge compressed string of
AkC .
The compression program is the
zlib
compress and uncompress. The
uncompress function requires that the caller know the expected uncompressed
size. This is true for RVP900 reads, because the reader always specifies the
read size.
• Version —Sends the IRIS version.
Read Data Available
(
RDAV )
Example:
RDAV|100|2|
means read up to 100 bytes of data from the RVP902 in
individual DMA transfers of 2 bytes each.
Before each read, the status is checked to see if there is more data available. If
not, the read stops, and the number of bytes read is returned. This is merely a
performance enhancing command, since the same feature is available by using
the
READ
and
STAT
commands.
Open the Connection for I
and O
(
OPEN )
Example: OPEN means switch from open for "info only" mode to open for I/O.
If the signal processor is in use by another device, you get an error in response to
this command. Multiple clients are allowed to connect for info only, but only one
can do I/O. If you run
DspExport with the -803 command line option, you get
the legacy behavior, which means that every connection automatically sends the
OPEN command.
There is no reverse command to switch back to open for info only. There is also no
such library call in the driver.
Read Zcal Information
( RCAL )
Example: ZCAL means read the dsp_refl_cal structure from RVP900 and
send it back in an ASCII name=value pair format.
This is the structure configured by
Zauto and Zcal .
The configuration is served to all clients using RVP900.
Reset Kernel FIFOs
(
RKFF )
Example: RKFF|2| means reset the kernel FIFOs on the RVP900.
The argument specifies which direction FIFOs to reset.
Chapter 3 – Functional Description
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