Omron SYSMAC C Series Operation Manual page 167

Data Exchange with CPU Unit
m
words
Example:
9
words
CPU Unit
156
turned OFF and then ON, or until the Unit is restarted. This value is turned OFF
when the power is turned OFF and then ON or when the Unit is restarted.
When the Number of Words Transferred is Greater than 1
First allocated I/O address
Transfer source address
Number of words transferred y0002
CPU Unit
(See
First RAM
note.)
address: a
Write
m–1
words
Note The specified first RAM address is not set in the Read Pointer (address 12) in RAM.
Allocated I/O: 0002, 0003
Write source first address
Number of words transferred
CPU Unit
First RAM
address: 01
(See
note.)
8
words
Using the I/O READ Instruction, READ
The READ instruction reads the specified number of words by using the content
of the Read Pointer (address 12) in RAM of the Analog Output Unit as the first
RAM address.
Data destination start address
Allocated I/O start address + 1
Number of words transferred
Analog Output Unit (Allocated I/O: n, n+1)
Address
Read
m
words
Read
Pointer
(m – 1) words starting from word S+1 are written
by using the content of word S as the first RAM
address of the Analog Output Unit. Use this
instruction when writing parameters and
conversion data directly to the Unit.
Analog Output Unit (Allocated I/O: n, n+1)
Address
Analog Output Unit
Address
Write
The READ instruction uses the value of the Read
Pointer in RAM as the first RAM address to read data
from m words and write it to words D to D+(m–1).
Before executing the READ instruction, set the value of
the Read Pointer in the WRIT instruction with the
number of words transferred set to 1.
Set using the WRIT instruction with the number of
words transferred set to 1.
Section 9-3