Rockwell Automation 2080-LC10-12DWD Micro810 Programmable Controllers User Manual - Manual (Page 44)

36 Rockwell Automation Publication 2080-UM001D-EN-E - September 2012
Chapter 6 Program Execution in Micro800
Memory Allocation Available memory on Micro810 controllers is shown in the table below.
These specifications for instruction and data size are typical numbers. When a
project is created for Micro800, memory is dynamically allocated as either
program or data memory at build time. This means that program size can exceed
the published specifications if data size is sacrificed and vice versa. This flexibility
allows maximum usage of execution memory. In addition to the user defined
variables, data memory also includes any constants and temporary variables
generated by the compiler at build time.
The Micro800 controllers also have project memory, which gets downloaded by
the Connected Components Workbench software. This embedded file is a copy
of the entire downloaded project, including comments and symbolic variable
names. If too many comments or variable names are contained in the project, a
compile error may occur referring to “embedded file size too large.” If this occurs,
reduce the number of comments and variables in the project.
Guidelines and Limitations Here are some guidelines and limitations to consider when programming a
Micro800 controller using Connected Components Workbench software:
• Each program/Program Organizational Unit (POU) can use up to 64 Kb
of internal address space. It is recommended that you split large programs
into smaller programs to improve code readability, simplify debugging and
maintenance tasks.
System Time Variable for Programmed Cycle Time
Variable Type Description
__SYSVA_TCYCYCTIME TIME Programmed cycle time.
Note: Programmed cycle time only accepts values in
multiples of 10 ms. If the entered value is not a
multiple of 10, it will be rounded up to the next
multiple of 10.
Memory Allocation for Micro810 Controllers
Attribute Micro810 12-point
Program steps
(1)
(1) Estimated Program and Data size are “typical” – program steps and variables are created dynamically.
1 Program Step = 12 data bytes.
2 K
Data bytes 2 KB