Vaisala RVP900, Руководство пользователя, Страница: 237 / 484

8. Host Computer Commands
8.1 Host Computer Command Overview
RVP includes a set of digital commands that the host computer must use to set up and
control the RVP900 processor for recording data.
Commands consist of an initial command word containing an opcode in the low five bits. If
additional arguments are required, they are listed as
Input 1 , Input 2 , and so on. If the
command produces output, those words are listed as Output 1 , Output 2 , and so on.
Often each word is broken down into independent fields, each consisting of one or more
bits. All data transferred to or from RVP900 are in the form of 16-bit words.
Unless otherwise noted, the command descriptions describe set bits.
More Information
‣
Output Data (page 47)
8.1.1 Setting-up Data Acquisition and Processing
Although the internal RVP900 tables and parameters are set to reasonable values on power-
up, you usually need to modify the default information to meet your needs.
1. On power-up, issue IOTEST to ensure that the interface connections are all intact.
2. Check the diagnostic result registers from GPARM to verify that RVP900 passes all
internal checks.
3. Establish trigger and pulse width using the SETPWF commands.
4. Chose range bin placement and processor options using LRMSK and SOPRM .
5. Take receiver noise samples with SNOISE .
The noise levels are not automatically sampled on power-up, you must issue SNOISE at
least once.
6. If clutter filters are needed, issue LFILT .
7. If data rays are to be synchronized with antenna motion, issue LSYNC to specify a table
of antenna angles.
Chapter 8 – Host Computer Commands
235