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Entry type: FAQ Entry ID: 88779859, Entry date: 03/06/2014

How do you configure the module parameters and address the HW_CONNECT variable to connect the RF180C/ ASM456 to the S7-1200/ S7-1500 CPU with the "Ident Instructions" block library?

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This FAQ response describes what you should watch out for when connecting the interface modules RF180C and ASM456 to a SIMATIC S7-1200/ S7-1500 CPU by means of the "Ident Instructions" block library.
The same "Ident Instructions" block library is used as for the interface module RF120C. The detailed description of this is available in Entry ID: 77485950.


  1. Configure the hardware.
  2. Go to "Devices & Networks" and mark the RF180C/ ASM456 device.
  3. Switch to "Device View > Properties > Module Parameters" and set the module parameters as shown in the figure below (for RF300, for example).

    Fig. 01

  4. When setting the parameters of the library blocks it is necessary to configure an "Address" parameter of the variable "HW_CONNECT_VAR". The values required for this parameter are described below.
    • HW_ID:
      Hardware identifier of the "2xRS422 Channels RFID" in the RF180C/ ASM456.
      Mark "2xRS422 Channels RFID"; the hardware identifier is displayed in the "Properties" tab. 
      Channel used of the RF180C/ASM456.
    • LADDR:
      IO address of the RF180C/ ASM456.
      This address is displayed in the "I address" field of the device overview of the RF180C/ ASM456.

    Fig. 02   

If you use a different interface module instead of the RF120C, then you must use the specific Reset block (for example, "Reset_RF300"), and not the general Reset block ("Reset_Reader").

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