Campbell CR5000, Руководство оператора

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CR5000 Overview
OV-5
OV1.3 Power Supply and AC Adapter
The CR5000 has two base options the low profile without any power supply
and the lead acid battery power supply base. The low profile base requires an
external DC power source connected to the Power In terminal on the panel.
The battery base has a 7 amp hour battery with built in charging regulator and
includes an AC adapter for use where 120 VAC is available (18 VAC RMS
output). Charging power can also come from a 17-28 VDC input such as a
solar panel. The DCDC18R is available for stepping the voltage up from a
nominal 12 volt source (e.g., vehicle power supply) to the DC voltage required
for charging the internal battery.
OV2. Memory and Programming Concepts
OV2.1 Memory
The CR5000 has 2MB SRAM and 1MB Flash EEPROM. The operating
system and user programs are stored in the flash EEPROM. The memory that
is not used by the operating system and program is available for data storage.
The size of available memory may be seen in the status file. Additional data
storage is available by using a PCMCIA card in the built in card slot.
OV2.2 Measurements, Processing, Data Storage
The CR5000 divides a program into two tasks. The measurement task
manipulates the measurement and control hardware on a rigidly timed
sequence. The
processing task processes and stores the resulting
measurements and makes the decisions to actuate controls.
The measurement task stores raw Analog to Digital Converter (ADC) data
directly into memory. As soon as the data from a scan is in memory, the
processing task starts. There are at least two buffers allocated for this raw
ADC data (more under program control), thus the buffer from one scan can be
processed while the measurement task is filling another.
When a program is compiled, the measurement tasks are separated from the
processing tasks. When the program runs, the measurement tasks are
performed at a precise rate, ensuring that the measurement timing is exact and
invariant.
Processing Task: Measurement Task:
Digital I/O task
Read and writes to digital I/O ports
(ReadI/O, WriteI/O)
Processes measurements
Determines controls (port states) to set next scan
Stores data
Analog measurement and excitation sequence and
timing
Reads Pulse Counters
Reads Control Ports (GetPort)
Sets control ports (SetPort)