Other Services And Properties - Siemens SIMATIC NET S7-1200 Operating Instructions Manual

Application and properties

1.2 Other services and properties

Table 1- 1 DNP3: Byte assignment of the status byte for DNP3 data points
Bit 7
Flag name -
Meaning -
(always 0)
Bit status
Table 1- 2 IEC: Byte assignment of the status byte for IEC data points
Bit 7
Flag name -
Meaning -
(always 0)
Bit status
1.2 Other services and properties
Other services and properties
● Data point configuration
Due to the data point configuration in STEP 7, programming program blocks in order to
transfer the process data is unnecessary. The individual data points are processed one-
to-one in the control system.
● Security functions (DNP3 only)
The DNP3 CP can use the security functions specified in the DNP3 protocol and
therefore secure communication in the DNP3 network, including the following:
– Secure authentication (SA) of the communications partner
– Logging of security events: Successful and failed authentication, key exchange,
You enable the security functions in the STEP 7 configuration with the required options.
10
6 5
- -
- -
(always 0) (always 0)
6 5
- SB
substituted
- Substitute
value
(always 0)
1
The DNP3 CP checks whether the communications partner has the right to access the
DNP3 CP.
Formation of the Message Authentication Code (MAC) using symmetrical (pre-shared
key, PSK) or asymmetrical cryptography (public/private keys)
Use of IPsec for transferring the key
statistical counters
4 3
LOCAL_- DISCONTI-
FORCED NUITY
Local Counted
operator value
control overflow
before
reading the
value
1 1
4 3
- CY
carry
- Counted
value
overflow
before
reading the
value
(always 0)
1
Operating Instructions, 02/2014, C79000-G8976-C312-02
2 1
OVER_- RESTART
RANGE
Value Value not
range updated
exceeded, after start
analog
value
1 1
2 1
OV NT
overflow not topical
Value Value not
range updated
exceeded,
analog
value
1 1
CP 1243-1 DNP3, CP 1243-1 IEC
0
ONLINE
Value is
invalid
1
0
IV
invalid
Value is
invalid
0