Cj2 Cpu Unit Features - Omron CJ2 CPU UNIT SOFTWARE User Manual

1 Overview
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CJ2 CPU Unit Features

Fast, with Large Memory Capacity
High-speed Processing
High-speed processing is possible for basic instructions (0.016 µs min. for CJ2H and 0.04 µs min.
for CJ2M), special instructions (0.05 µs min. for CJ2H and 0.06 µs min. for CJ2M), and immediate
refreshing (0.99 µs min. for CJ2H and 1.26 µs min. for CJ2M).
Large Program Capacity
The CJ2 CPU Units provide a large program capacity of up to 400 Ksteps.
Special Function Block Definition Area (CJ2M Only)
With a CJ2M CPU Unit, a special area called the FB Program Area is provided to store function
block definitions. (The FB Program Area holds 20K steps.) This allows you to use function blocks to
make program components and structures from previous programs while reducing the usage of the
User Program Area. And any function block definitions that would exceed the FB Program Area are
stored in the User Program Area.
Large Data Memory Capacity
The CJ2 CPU Units provide a large EM Area capacity of up to 800 Kwords (25 banks).
Up to 128 Cyclic Tasks
The user program can be divided into up to 128 tasks. Using smaller task programs makes it easier
to structure programs and contributes to shorter cycle times.
Better Execution Performance for Interrupt Tasks (CJ2H CPU Unit with Unit
Version 1.1 or Later)
With CJ2H CPU Units with unit version 1.1, overhead time for interrupt tasks is approximately 20%
less than for unit version 1.0 even for normal usage. Also, by using High-speed interrupt function, it
is possible to improve execution performance as shown below with certain restrictions.
• Greatly reduce overhead time for interrupt tasks (interrupt task startup time + return time to cyclic
tasks).
Example: For I/O interrupt tasks, the time for normal operation is 37 µs but the time is 25 µs if
• Minimum Interval Setting of 0.1 ms for Scheduled Interrupt Tasks
(For unit version 1.0, the minimum interval is 0.2 ms.)
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High-speed interrupt function is used.
CJ2 CPU Unit Software User's Manual