Omron CS1W-MC221 -, Operation Manual

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Overview of G-language Programs in the MC Unit Section 1-7
2. Data can be read or written by directly specifying MC Unit RAM addresses
in IORD or IOWR instructions in a ladder diagram program.
Use IORD and IOWR instructions to change or read data while the CPU
Unit operations are in progress.
3. Position data can be transferred indirectly by using IOWR in a ladder dia-
gram program to write specified data to the MC Unit’s command area. Up
to 2,000 data items (6,000 words) can be transferred in this way.
For details, refer to SECTION 4 Data Transfer and Storage.
1-7 Overview of G-language Programs in the MC Unit
1-7-1 Programs and Tasks
The CS1W-MC421 MC Unit can execute up to four tasks (tasks 1 to 4), and
the CS1W-MC221 can execute one or two (tasks 1 to 2). (A task is a unit of
execution for a program.)
By executing two or four tasks at the same time, the MC Unit can perform the
same functions as two or four controllers.
The number of tasks and axes to be used are set in advance using CX-Motion
to edit unit parameters.
Number of Tasks and Axes
The X and Y axes can be used with the CS1W-MC221, and the X, Y, Z, and U
axes can be used with the CS1W-MC421. Each axis can be used in only one
task, i.e., any axis assigned to one task cannot be used in another task.
Example: 4 Tasks and 4 Axes
Example 2: 2 Tasks and 3 Axes
MC Unit
CPU Unit
Ladder diagram program
System parameters
Position data
Monitoring/
command area
Task 1 :
X axis Task 2:
Y axis Task 3 :
Z axis Task 4:
U axis
Task 1 :
X, Y axis Task 2:
Z axis Task 1:
X, Y axis Task 2:
Z axis