Omron SYSMAC C500-NC113 Operation Manual page 22

1-5 Exchanging Data
CPU Unit
Data area
I/O allocation
Beginning
Command (in Program Mode)
word n
Data
DM area Address N
Address M
Command (in RUN
or Monitor Mode)
IR area
* 5 words for the NC113 Unit.
IR area
** 8 words for the NC113 Unit
Explanation
1, 2, 3...
The Position Control Unit exchanges data with the CPU Unit as shown in the fol-
lowing diagram.
I/O refresh
Intelligent I/O Write
instruction
(Positioning data)
Intelligent I/O Write
instruction
9 wds*
(START command, etc.)
Intelligent I/O Read
instruction
(PCU status)
15 wds**
1. I/O Allocation
The Position Control Unit occupies two CPU Unit output words (32 bits).
During an I/O refresh (when the CPU Unit is in Program Mode), one of those
words is used for transferring commands from the CPU Unit to the PCU, and
the other is used for transferring PCU status to the CPU Unit.
2. Data
The positioning data to be stored at the PCU is transferred from the CPU
Unit to the PCU, along with the addresses for the individual items of data, by
means of the PCU's Intelligent I/O Write instruction. The data is then stored
in the PCU's internal RAM according to the header addresses.
Section
Position Control Unit
I/O allocation
Status
Internal RAM
Command
interpretation
Status Area
1-5