At a Glance

Some Bits and Words Are Not Implicitly Exchanged (at Each PLC Cycle) Between the Modules and the PLC Processor. These bits and words are grouped into 3 families: information on status (STATUS), command (CMD) and parametering (PARAM) and are explicitly exchanged.

Explicit exchanges are normally made by program, but the user can also initiate such an exchange by clicking on a button, located in an operator screen.

The explicit exchange tab allows you to define the exchange characteristics:

  • to select an explicit exchange instruction,

  • to select the text of the button,

  • to select the address of the channel to which the exchange will be applied,

  • To display the parameters associated with the instruction.

NOTE: Only the exchanges of objects associated with a channel are authorized.

Explicit Exchanges Attributes Setting Screen

The screen below allows you to set the attributes of an explicit exchange object.

Description

The table below describes the settings that you may define.

Field

Description

Instruction

Explicit exchange instruction:

  • READ_STS: reading of channel status words contained in the module and updating the data in the PLC.

  • WRITE_PARAM: writing of channel parametering words, contained in the module.

  • READ_PARAM: reading of channel parametering words, contained in the module.

  • SAVE_PARAM: backup in a specific memory space of channel parametering words, contained in the module.

  • RESTORE_PARAM: restoration of values saved by SAVE_PARAM.

  • WRITE_CMD: implements the execution of a command on a channel.

Text

Text that appears on the button.

Channel address

Remote: this box is checked if the module to be interrogated is on a remote station.

In rack: this box is checked if the module to be interrogated is on the rack of the local station.

Address of the module channel. This address has the form:

  • \bus.station\rack.location.channel:

    • bus: bus number (shaded if local station),

    • station: number of the device connection point (shaded if local station),

    • rack: station rack number,

    • position: position of the module on the rack,

    • channel: channel number.

NOTE: For Write_Param and for Write_Cmd we have to modified the associated %MW by animation table or another one (by program, by 'Entry field' through operator screen, ...) before sending the instruction (Write_Param or Write_Cmd) through the Operator screen.