Advanced Topics - Siemens SIMATIC S7-200 System Manual

Advanced Topics

Understanding the Configuration Table
The Modem Expansion wizard has been developed to make modem applications easy by
automatically generating the configuration table based upon the answers you give about your
system. Configuration table information is provided for advanced users who want to create their
own Modem module control routines and format their own messages.
The configuration table is located in the V memory area of the S7-200. In Table 10-12, the Byte
Offset column of the table is the byte offset from the location pointed to by the configuration area
pointer in SM memory. The configuration table information is divided into four sections.
The Configuration Block contains information to configure the module.
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The Callback Telephone Number Block contains the predefined telephone numbers allowed
-
for callback security.
The Message Telephone Number Block contains the telephone numbers used when dialing
-
messaging services or CPU data transfers.
The Message Block contains the predefined messages to send to the messaging services.
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Table 10-12 Configuration Table for the Modem Module
Configuration Block
Byte Offset
0 to 4
5
6
7
8
9
10
11
12
13
14
15
16 to 23
Description
Module Identification - - Five ASCII characters used for association of the configuration table
to an intelligent module. Release 1.00 of the EM 241 Modem module expects "M241A".
The length of the Configuration Block - - Currently 24.
Callback telephone number length - - Valid values are 0 through 40.
Messaging telephone number length - - Valid values are 0 through 120.
Number of callback telephone numbers - - Valid values are 0 through 250.
Number of messaging telephone numbers - - Valid values are 0 through 250.
Number of messages - - Valid values are 0 through 250.
Answer ring number - - Valid values are 0 through 20.
Modbus RTU address - - Valid values are 0 through 247.
This byte contains the enable bits for the features supported.
MSB
7 6 5 4 3 2
PD CB PW MB BD 0
PD - - 0 = tone dialing
CB - - 0 = callback disabled
PW - - 0 = password disabled
MB - - 0 = PPI protocol enabled
BD - - 0 = blind dialing disabled
Bits 2, 1 and 0 are ignored by the module
Reserved
Attempts - - This value specifies the number of times the modem is to attempt to dial and
send a message before returning an error. A value of 0 prevents the modem from dialing
out.
Password - - Eight ASCII characters
Creating a Program for the Modem Module
LSB
1 0
0 0
1 = pulse dialing
1 = callback enabled
1 = password enabled
1 = Modbus protocol enabled
1 = blind dialing enabled
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