Structure Of The Network Parameter Block (Npb); Structure Of The Network Data Block (Ndb); Table 8 Structure Of The Npb - Siemens SIMATIC NET CP 243-1 IT Technical Manual

Configuration
4.4.3

Structure of the Network Parameter Block (NPB)

The CP 243-1 IT creates this data block automatically based on the current record
of the network parameters. It contains the currently used TCP/IP parameter values
if the CP 243-1 IT was configured correctly. If configuration errors occurred, the
NPB does not contain valid entries.
Byte Offset
in Variable
Memory
108-109 Common flag byte
Bit [0] Duplex mode
Bit [1] Data rate
Bit [2] Auto negotiation
Bit [3] BOOTP
Bit [4-15] Not used
110-113 Current IP address
114-117 Current subnet mask
118-121 IP address of the current
gateway
122-127 MAC address
Table 8
4.4.4

Structure of the Network Data Block (NDB)

The NDB is created by the Internet wizard in STEP 7 Micro/WIN 32. The read/write
jobs possible for clients are configured in this data block. Up to 32 read/write jobs
can be configured for each of the 8 possible S7 transmission channels. When the
CP 243-1 IT is the server on a channel, there is no entry in the NDB structure for
this channel.
74
Description
0: Half duplex
1: Full duplex
0: 10 Mbit/sec
1: 100 Mbit/sec
0: No auto negotiation
1: Auto negotiation
0: Use configured
network parameters.
1: BOOTP
Structure of the NPB
Calculation of the Data Format
Value
Varies with the cur- 2 bytes, hex
rent configuration
Varies with the cur- 4 bytes, hex
rent configuration
Varies with the cur- 4 bytes, hex
rent configuration
Varies with the cur- 4 bytes, hex
rent configuration
Read from hard- 6 bytes, hex
ware
03/03
Example
16#04: Auto nego-
tiation
Use configured
network parame-
ters.
192.12.45.23:
16#C00C2D17
255.255.255.0:
16#FFFFFF00
192.12.45.24:
16#C00C2D18
16#080006021F04
08-00-06-02-1F-04
CP 243-1 IT
J31069-D0429-U001-A0-7618