Vaisala RVP900

USER’S MANUAL__________________________________________________________________
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3.3.4.3.2 Write Command (WRIT)
Example: "WRIT|<data>", where <data> is some binary data. This data is
written to the RVP900. Again, the data size should be even.
3.3.4.3.3 Read Status Command (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 either "Ack|0", "Ack|1", or a "Nak". This is the equivalent of the
dspr_status() call in the dsp library.
3.3.4.3.4 Set Information Command (INFO)
Example:
"INFO|ByteOrder=LittleEndian,WillCompress=1,Version=7.32". This
command can be used to inform RVP902 DspExport about the host
computer. Current options available 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 only thing compressed is the data from
normal READ commands. If it 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.
3.3.4.3.5 Read Data Available Command (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 command and the STAT command.