Ov2. Memory And Programming Concepts; Ov2.1 Internal Memory - Campbell CR510 Operator's Manual

time when power is disconnected. The clock
and Static Random Access Memory (SRAM)
are powered by an internal lithium battery.
OV2. MEMORY AND PROGRAMMING
CONCEPTS

OV2.1 INTERNAL MEMORY

The standard CR510 has 128 K of Flash
Electrically Erasable Programmable Read Only
Memory (EEPROM) and 128 K Static Random
Access Memory (SRAM). The Flash EEPROM
stores the operating system and user programs.
RAM is used for data and running the program.
Data Storage can be expanded with an optional
Flash EEPROM (Figure OV2.1-1). The use of
the Input, Intermediate, and Final Storage in the
measurement and data processing sequence is
shown in Figure OV2.1-2. The five areas of
SRAM are:
1. System Memory - used for overhead tasks
such as compiling programs, transferring
data, etc. The user cannot access this
memory.
2. Program Memory - available for user
entered programs.
3. Input Storage - Input Storage holds the
results of measurements or calculations.
The ∗6 Mode is used to view Input Storage
locations for checking current sensor
readings or calculated values. Input
Storage defaults to 28 locations. Additional
locations can be assigned using the ∗A
Mode.
4. Intermediate Storage - Certain Processing
Instructions and most of the Output
Processing Instructions maintain
intermediate results in Intermediate
Storage. Intermediate storage is
automatically accessed by the instructions
and cannot be accessed by the user. The
default allocation is 64 locations. The
number of locations can be changed using
the ∗A Mode.
5. Final Storage - Final processed values are
stored here for transfer to printer, solid state
Storage Module or for retrieval via
telecommunication links. Values are stored
in Final Storage only by the Output
Processing Instructions and only when the
Output Flag is set in the user's program.
Approximately 62,000 locations are
allocated to Final Storage on power up.
This number is reduced if Input or
Intermediate Storage is increased.
While the total size of these areas remains
constant, memory may be reallocated between
the areas to accommodate different
measurement and processing needs (∗A Mode,
Section 1.5).
CR510 OVERVIEW
OV-3