Campbell CR800 Series, Руководство оператора

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Section 8. Operation
408
1
See
TABLE: CR800 SRAM Memory
(p. 408,
http://www.
)
2
Flash is rated for > 1 million overwrites.
3
Serial flash is rated for 100,000 overwrites (50,000 overwrites on 128 kB units). CRBasic program
functions that overwrite memory should use the CRD: or USR: drives to minimize wear of the CPU: drive.
CR800 SRAM Memory
Use Comments
Static Memory Operational memory used by the operating system. Rebuilt at power-up,
program re-compile, and watchdog events.
——————————
——
Operating Settings and
Properties
"Keep"
(p. 503)
memory. Stores settings such as PakBus address, station
name, beacon intervals, neighbor lists, etc. Also stores dynamic properties
such as the routing table, communication timeouts, etc.
——————————
——
CRBasic Program
Operating Memory
Stores the currently compiled and running user program. This sector is
rebuilt on power-up, recompile, and watchdog events.
——————————
——
Variables & Constants
Stores variables used by the CRBasic program. These values may persist
through power-up, recompile, and watchdog events if the
PreserveVariables instruction is in the running program.
——————————
——
Final-Storage Memory
Stores data. Fills memory remaining after all other demands are satisfied.
Configurable as ring or fill-and-stop memory. Compile error occurs if
insufficient memory is available for user-allocated data tables. Given
lowest priority in SRAM memory allocation.
——————————
——
Communication Memory 1
Construction and temporary storage of PakBus packets.
——————————
——
Communication Memory 2
Constructed Routing Table: list of known nodes and routes to nodes.
Routers use more space than leaf nodes because routes to neighbors must
be remembered. Increasing the PakBusNodes field in the Status table will
increase this allocation.
——————————
——
USR: drive
≤ 3.6 MB (4 MB Mem)
≤ 1.5 MB (2 MB Mem)
Optionally allocated. Holds image files. Holds a copy of final-storage
memory when TableFile() instruction used. Provides memory for
FileRead() and FileWrite() operations. Managed in
File Control
(p. 416).
Status reported in
Status
table fields
USRDriveSize
(p. 551)
and
USRDriveFree
(p. 551).