Campbell CR3000 Micrologger, Руководство оператора

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Section 8. Operation
466
File System Error Codes
Error Code Description
42
Controller failure error
43 Pathname exceeds _MAX_PATHNAME
8.8.8 Memory Q & A
Q: Can a user create a program too large to fit on the CPU: drive (>100k) and
have it run from the CRD: drive (memory card)?
A: The program does not run from the memory card. However, a very large
program (too large to fit on the CPU: drive) can be compiled into CR3000 main
memory from the card if the binary form of the compiled program does not
exceed the available main memory
(p. 442).
8.9 Data Retrieval and Comms — Details
Related Topics:
• Data Retrieval and Comms — Quickstart
(p. 40)
• Data Retrieval and Comms — Overview
(p. 80)
• Data Retrieval and Comms — Details
(p. 466)
• Data Retrieval and Comms Peripherals — Lists
(p. 610)
Comms, in the context of CR3000 operation, is the movement of information
between the CR3000 and another computing device, usually a PC. The
information can be data, program, files, or control commands.
8.9.1 Protocols
The CR3000 communicates with datalogger support software
(p. 90)
and other
Campbell Scientific dataloggers
(p. 603)
using the PakBus
(p. 548)
protocol. See
Alternate Comms Protocols
(p. 468)
for information on other supported protocols,
such as TCP/IP, Modbus, etc.
8.9.2 Conserving Bandwidth
Some comms services, such as satellite networks, can be expensive to send and
receive information. Best practices for reducing expense include:
•
Declare Public only those variables that need to be public.
•
Be conservative with use of string variables and string variable sizes.
Make string variables as big as they need to be and no more; remember
the minimum is actually 24 bytes. Declare string variables Public and
sample string variables into data tables only as needed.