Siemens SIMATIC NET S7-CPs Configuring And Installing page 222

9 File Management and File Access with FTP
9.4 The Advanced CP as FTP client for S7 CPU data
9.4.1 Method
To transfer data using FTP, you create data blocks (file DBs) in the CPU of your S7
station (for structure, refer to Section 9.3.4).
The user program sends FTP jobs that are executed by the Advanced CP as an
FTP client. Depending on the module type of the Advanced CP, you can use
FC40...44 or FB40 in the user program (see Section 9.4.4).
The data are transferred on FTP connections. FTP connections are special TCP
connections that you configure in STEP 7 / NetPro.
In the job, among other things, you specify the IP address of the FTP server, the
storage location of the file on the FTP server and the file name along with access
information.
The following schematics illustrate how the function works when using FC40...44
or FB40.
FTP client:
S7 station with Advanced CP
S7 − 400
S7 − 300
File DBs
DB127
DB243
DB244
Figure 9-3 How FTP data transmission works when using FC40...44
A−222
FTP connection
FTP_RETRIEVE
Header
User data
User program
CALL FC40
CALL FC42
CALL FC44
FTP server
FTP_STORE
S7-CPs for Industrial Ethernet Configuring and Commissioning
Release 07/2010
C79000−G8976−C182−10