Campbell Scientific CSAT3 3-D Sonic Anemometer - Manual (Page 29)

CSAT3 Three Dimensional Sonic Anemometer
10. Datalogger Programming using SDM
The CRBasic CSAT3 () and EDLOG SDM-CSAT3 (P107) instructions are
Input/Output instructions that control and retrieve data from the CSAT3.
These instructions are available on the CR3000, CR1000, CR5000,
CR800/850, CR9000(X), and CR23X, 21X (with CSAT3 PROMs), CR10X,
and CR10 (with CSAT3 PROMs or library special PROMs).
10.1 CRBasic CSAT3 () Instruction
The CSAT3 () instruction is a five parameter CRBasic instruction to control
and retrieve data from the CSAT3. The parameters for this instruction are
given in TABLE 10-1 and described in Section 10.3.
TABLE 10-1. CSAT3 () Instruction Parameters
CSAT3 (Dest,Reps,SDMAddress,Command,Option)
10.2 EDLOG SDM-CSAT3 (P107) Instruction
The SDM-CSAT3 (P107) is a four parameter instruction. The parameters are
given in TABLE 10-2 and described in Section 10.3.
TABLE 10-2. SDM-CSAT3 (P107) Instruction Parameters
Parameter
Number
Data
Type
Default
Description
01: 2 Reps
02: 2 SDM Address
03: 2 Option
04: 4 Ux Input Location
10.3 Datalogger Instruction Parameters
Dest: The destination variable to store the first of five data values to a
CRBasic datalogger. The variable must be declared as a float (default) with at
least five elements. The CSAT3 returns the following data after receiving the
“Trigger and Get Data” or “Get Data after a Group Trigger” command in the
“Command” parameter: u
x
, u
y
, u
z
, c or T
s
, and a diagnostic word, where u
x
, u
y
,
and u
z
are the wind speeds along the x, y, and z axes defined by the
anemometer head (see FIGURE 4-1), c is the speed of sound, and T
s
is the
sonic virtual temperature. The wind speed and the speed of sound are in units
of m s –1 , and T
s
is in degrees Celsius. If the Reps option is greater than 1, the
number of elements required in the destination variable is Reps ∗ 5.
Reps: The number of CSAT3s on the SDM bus that will be sequentially
addressed with the CSAT3()/SDM-CSAT3 (P107) instruction.
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