E_RFID_Command

  TYPE E_RFID_Command : (
    eRFC_Unknown        := 0,
    eRFC_GetReaderVersion,
    eRFC_GetConfig,
    eRFC_SetConfig,
    eRFC_GetInventory,
    eRFC_Polling,
    eRFC_TriggerOn,
    eRFC_TriggerOff,
    eRFC_AbortCommand,
    eRFC_ResetReader,
    eRFC_ReadBlock,
    eRFC_WriteBlock,
    eRFC_OutputOn,
    eRFC_OutputOff,
    eRFC_FieldOn,
    eRFC_FieldOff,
    eRFC_SendRawData,
    eRFC_ChangeDCType,
END_TYPE

The function block FB_RFIDReader of the TwinCAT PLC RFID library offers the above enumeration values at the eCommand input.
These are the available commands, such as reading or writing to a transponder. For details see description of the command set.