REV_XFER

Function Description

This EFB allows you to use the Hot Standby function. It searches (together with the other Hot Standby EFBs) the configuration of the respective Quantum PLCs for the required components. These components refer to hardware that is actually connected.

REV_XFER provides the ability to transmit 2 registers (%SW62/63) from the Standby PLC to the Primary PLC. The two registers EFB are used by the application program (in the first section) to register diagnostic information.

REV_XFER can only be used in the first executable section of the project. The parameter addresses TO_REV1 and TO_REV2 have to be in the Non-Transfer Area to prevent being overwritten by the Primary CPU.

NOTE: Take care that, if the PLC is in Offline mode, the reverse transfer will not transfer the data because the Hot Standby condition is no longer valid.

As additional parameters, EN and ENO are projected.

Appearance in FBD

Appearance in LD

Appearance in IL

Appearance:

CAL REV_XFER_Instance (TO_REV1:=Standby_PLC_FirstReg,
         TO_REV2:=Standby_PLC_SecondReg, HSBY=>HSBY_ConfFlag,
         PRY=>Primary_PLC_Flag, SBY=>Standby_PLC_Flag,
         FR_REV1=>FirstRevTransReg,
         FR_REV2=>SecondtRevTransReg)

Appearance in ST

Appearance:

REV_XFER_Instance (TO_REV1:=Standby_PLC_FirstReg,
         TO_REV2:=Standby_PLC_SecondReg, HSBY=>HSBY_ConfFlag,
         PRY=>Primary_PLC_Flag, SBY=>Standby_PLC_Flag,
         FR_REV1=>FirstRevTransReg,
         FR_REV2=>SecondtRevTransReg);

Parameter Description

Description of input parameters:

Parameter	Data type	Description
`TO_REV1`	`INT`	Describes the first reverse transfer register if this PLC is the Standby PLC. Data in this register are transferred from the Standby CPU to the Primary CPU at each scan.
`TO_REV2`	`INT`	Describes the second reverse transfer register if this PLC is the Standby CPU. Data in this register are transferred from the Standby CPU to the Primary CPU at each scan.

Description of the output parameters:

Parameter	Data type	Description
`HSBY`	`BOOL`	1 = This is a Hot Standby configuration. 0 = This is not a Hot Standby configuration.
`PRY`	`BOOL`	1 = This PLC is the Primary CPU PLC. 0 = This PLC is not the Primary CPU PLC.
`SBY`	`BOOL`	1 = This PLC is the Standby CPU PLC. 1 = This PLC is not the Standby CPU PLC.
`FR_REV1`	`INT`	Content of first reverse transfer register %SW62. Output only if `HSBY` is 1.
`FR_REV2`	`INT`	Content of second reverse transfer register %SW63. Output only if `HSBY` is 1.