Mitsubishi Electric MELSEC Q Series User Manual page 213

(5) Link device access function
The dedicated function is used from the user program to access the link device.
There are the following 3 methods to access the link device(s) of the controlled network module from the C
Controller module.
C Controller module
User program
Transmission type
A method to access internal user device(s) of the C
Access by link Controller module from the user program.
1)
refresh function Data in the internal user device(s) are communicated to
the link device of the network module by link refreshing.
A method to directly access network module link
2) Direct access
device(s) from the user program.
Buffer memory A method to access network module buffer memory from
3)
access the user program.
*1 : For CC-Link module, setting of block data assurance per station is enabled by buffer memory access.
● Proper use of transmission types
For infrequently used devices, excluding them from the link refresh range without using access by link refresh may
reduce the link refresh time. (Page 249, Section 13.5.3)
Link device access methods available from the C Controller module to each controlled network module are listed
below.
CC-Link IE Controller
Transmission type
Access by link
1)
refresh function
2) Direct access
Buffer memory
3)
access
Link refresh
Internal user
1)
device
Direct access
2)
Buffer memory access
3)
Description
MELSECNET/H
Network


–
CHAPTER 13 FUNCTIONS ACCESSED VIA A NETWORK MODULE
network module network module
Link Link
device scan
Buffer memory
Appropriate data
• Frequently used link device
• Link device that requires block
data assurance per station
• Infrequently used link device
CC-Link IE Field
Network
 
 
– 
Link
device
Reference
Page 212,
Section
*1
13.2.1
Page 217,
Section
13.2.2
Page 219,
Section
13.2.3
: Available –: N/A
CC-Link
–


211
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