Siemens CP 243-1 IT, Technical Manual

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Configuration 03/03
CP 243-1 IT
J31069-D0429-U001-A0-7618
74
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
Description Calculation of the
Value
Data Format Example
108-109 Common flag byte
Bit [0] Duplex mode
0:
Half duplex
1: Full duplex
Bit [1] Data rate
0: 10 Mbit/sec
1: 100 Mbit/sec
Bit [2] Auto negotiation
0: No auto negotiation
1: Auto negotiation
Bit [3] BOOTP
0: Use configured
network parameters.
1: BOOTP
Bit [4-15] Not used
Varies with the cur-
rent configuration 2 bytes, hex 16#04: Auto nego-
tiation
Use configured
network parame-
ters.
110-113 Current IP address Varies with the cur-
rent configuration 4 bytes, hex 192.12.45.23:
16#C00C2D17
114-117 Current subnet mask Varies with the cur-
rent configuration 4 bytes, hex 255.255.255.0:
16#FFFFFF00
118-121 IP address of the current
gateway Varies with the cur-
rent configuration 4 bytes, hex 192.12.45.24:
16#C00C2D18
122-127 MAC address Read from hard-
ware 6 bytes, hex 16#080006021F04
08-00-06-02-1F-04
Table 8 Structure of the NPB
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.