Description:
The FAQ concerns those FMs that exchange data with an HMI device. The following modules are concerned:
 

FM type	MLFB
FM353  F. STEPPER MOTOR	6ES7353-1AH01-0AE0
FM354  F. SERVO MOTOR	6ES7354-1AH01-0AE0
FM357  4 AXIS CONTROL	6ES7357-4AH01-0AE0

CPU-dependent FM addressing
In the S7-300 CPUs there are two different architecture models with regard to the bus, in which the FM addressing is displayed differently to the user in each case. A difference is to be made between CPUs with and without combined MPI/DP interface.

• CPUs without combined MPI/DP interface
  In HW Config the MPI address "MPI addr.[CPU] + 1" is entered automatically for the FM module. This value could also be changed by the user if necessary.
  
  
  Fig. 01
  
  
  This case holds for all configurations with CPUs that are not included in the table below.
   
• CPUs with combined MPI/DP interface
  In HW Config the MPI address of the FM module is not displayed. The user does not know which FM address is to be parameterized in the HMI configuration tool.
  
  
  Fig. 02
  
  
  This case holds for all configurations with CPUs that are included in the table below.
   

CPUs with integrated DP interface

CPU 315-2 PN/DP

CPU 315F-2 PN/DP

CPU 317 (all types)

CPU 318 (all types)

CPU 319 (all types)

HMI <-> FM connection configuration for CPUs without combined MPI/DP interface:
(address data of the following examples (screenshots): CPU: MPI=2, Slot=2; FM: MPI=3, Slot=4;)

Connection configuration with ProTool or WinCC flexible permits two access paths to the FM:

• Access path 1
  
  
  Fig. 03
  
  
  
  Fig. 04
  
  
• Access path 2
  
  
  Fig. 05
  
  
  
  Fig. 06
   

HMI <-> FM connection configuration for CPUs with combined MPI/DP interface:
(address data of the following examples (screenshots): CPU: MPI=2, Slot=2; FM: Slot=4;)

• There is only Access path 1 to the FM.
  
  
  Fig. 07
  
  
  
  Fig. 08
   

Note:
For the examples in the masks above the configuration tool concerned was integrated in each case in STEP 7. In these cases entry of the FM address (MPI, slot and BGT numbers) is automatic and cannot be changed by the user as long as you click to select the FM or access point via which the FM is to be reached. Manual input of the FM address data is possible by clicking "Define the parameters yourself" (ProTool) or "No station" for station selection (WinCC flexible). In the case of a nonintegrated configuration tool you must always specify the FM address data manually.