Omron SYSMAC C500-NC113 Operation Manual page 131

9-1 Programming Background
9-1-1 Overall Configuration for Exchanging Data
CPU Unit
Memory
Area
Allocated I/O
Command (in
Leading n
Program Mode)
n+1
DM area
Address N
Address M
Command (in RUN
or Monitor Mode)
IR area
m 0 0
m+8
* 5 words for the NC113
IR area
s
s+14
** 8 words for the NC113
Allocated I/O
Data
Commands
The Position Control Unit exchanges data with the CPU Unit as shown in the fol-
lowing illustration.
Data
Intelligent I/O Write
instruction (WRIT)
(Positioning data)
0 1
Intelligent I/O Write
instruction (WRIT)
(START
command, etc.)
9 words*
Intelligent I/O
Read command
15 words**
The Position Control Unit occupies two of the CPU Unit's output words (32 bits).
One of those words is used for transferring commands from the CPU Unit to the
Position Control Unit during I/O refreshing (when the CPU Unit is in Program
Mode). The other word is used for transferring the PCU status from the Position
Control Unit to the CPU Unit during I/O refreshing.
Positioning data to be stored at the Position Control Unit is transferred from the
CPU Unit to the Position Control Unit, along with the addresses in the Position
Control Unit, by the CPU Unit's Intelligent I/O Write command. The Position Con-
trol Unit stores the data in its internal RAM by address, based on the headers.
Commands such as START and ORIGIN SEARCH are transferred to the Posi-
tion Control Unit by the Intelligent I/O Write instruction. The Position Control Unit
interprets the commands and executes them.
I/O refresh
n
n+1
Address
N
M
(PCU status)
Section
Position Control Unit
Allocated I/O
Status
Internal RAM
Command
interpretation
Status area
9-1