Siemens SIMATIC S7-200 System Manual page 329

4. The Modem module supports two communications protocols: PPI protocol (to communicate
with STEP 7--Micro/WIN), and Modbus RTU protocol. Protocol selection is dependent on
the type of device that is being used as the remote communications partner. This setting
controls the communications protocol used when the Modem module answers a call and
also when the Modem module initiates a CPU data transfer. Select the appropriate protocol
and click Next>.
5. You can configure the module to send numeric and text messages to pagers, or Short
Message Service (SMS) messages to cellular telephones. Check the Enable messaging
checkbox and click the Configure Messaging... button to define messages and the
recipient's telephone numbers.
6. When setting up a message to be sent to a pager or cellular phone, you must define the
message and the telephone number. Select the Messages tab on the Configure Messaging
screen and click the New Message button. Enter the text for the message and specify any
CPU data values to insert into the message. To insert a CPU data value into the message,
move the cursor to the position for the data and click the Insert Data... button. Specify the
address of the CPU data value (i.e. VW100), the display format (i.e. Signed Integer) and the
digits left and right of the decimal point. You can also specify if the decimal point should be
a comma or a period.
-- Numeric paging messages are limited to the digits 0 to 9, the letters A, B, C and D,
and the asterisk (*). The maximum allowed length of a numeric paging message
varies by service provider.
-- Text messages can be up to 119 characters in length and contain any alphanumeric
character.
-- Text messages can contain any number of embedded variables.
-- Embedded variables can be from V, M, SM, I, Q, S, T, C or AI memory in the attached
CPU.
-- Hexadecimal data is displayed with a leading '16#'. The number of characters in the
value is based on the size of the variable. For example, VW100 displays as 16#0123.
-- The number of digits left of the decimal must be large enough to display the expected
range of values, including the negative sign, if the data value is a signed integer or
floating point value.
-- If the data format is integer and the number of digits right of the decimal point is not
zero, the integer value is displayed as a scaled integer. For example, if VW100 =
1234 and there are 2 digits right of the decimal point, the data is displayed as '12.34'.
-- If the data value is greater than can be displayed in the specified field size, the
Modem module places the # character in all character positions of data value.
7. Telephone numbers are configured by selecting the Phone Numbers tab on the Configure
Messaging screen. Click the New Phone Number... button to add a new telephone number.
Once a telephone number has been configured it must be added to the project. Highlight
the telephone number in the Available Phone Numbers column and click the right arrow box
to add the telephone number to the current project. Once you have added the telephone
number to the current project, you can select the telephone number and add a symbolic
name for this number to use in your program.
The telephone number consists of several fields which vary based on the type of
messaging selected by the user.
-- The Messaging Protocol selection tells the Modem module which protocol to use
when sending the message to the message service provider. Numeric pagers
support only numeric protocol. Text paging services usually require TAP (Telelocator
Alphanumeric Protocol). SMS messaging providers are supported with either TAP or
UCP (Universal Computer Protocol). There are three different UCP services normally
used for SMS messaging. Most providers support command 1 or 51. Check with the
SMS provider to determine the protocol and commands required by that provider.
-- The Description field allows you to add a text description for the telephone number.
Creating a Program for the Modem Module Chapter 10
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