Mitsubishi Electronics FX5 ユーザーズマニュアル

21 DEVICES

21.3 System Devices

215

Data register (D)

Device capable of storing numerical data.

Link register (W)

Device intended to be used as a CPU side device when refreshing word data between CPU module and network module.

Refreshing network module that uses link register (W)

Sends/receives data mutually between link registers (LW) in network module and link register (W) in the CPU module. Set
refresh range by parameters of the network module. Link registers not used for refresh can be used for other purposes.

Link special register (SW)

Word data such as communication and error detection status information of network modules is output to link special relays
within the network. Link special registers (SW) are devices intended to be used as a refresh destination for link special
registers within the network. Link special registers not used for refresh can be used for other purposes.

21.3

System Devices

System devices are devices for the system. Assignment/capacity are fixed and cannot be changed by the user.

Special relay (SM)

The PLC contains internal relays with fixed specifications, so it cannot be used in the program like a conventional internal
relay. It can however be turned ON/OFF to control the CPU module as needed. (Page 224 Special Relay List)

Special register (SD)

The PLC contains internal register with fixed specifications, so it cannot be used in the program like a conventional internal
register. Data, however, can be written to control the CPU module as needed. (Page 240 Special Register List)