Siemens SIMATIC S7-1200, Системное руководство

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97BPLC concepts
4.4 Data types
S7-1200 Programmable controller
90
System Manual, 11/2011, A5E02486680-05
DTL
DTL (Date and Time Long) data type uses a12 byte structure that saves information on date
and time. You can define DTL data in either the Temp memory of a block or in a DB. A value
for all components must be entered in the "Start value" column of the DB editor.
Table 4- 20 Size and range for DTL
Length
(bytes) Format Value range Example of value input
12 Clock and calendar
Year-Month-Day:Hour:Minute:
Second.Nanoseconds
Min.: DTL#1970-01-01-00:00:00.0
Max.: DTL#2554-12-31-23:59:59.999
999 999
DTL#2008-12-16-20:30:20.250
Each component of the DTL contains a different data type and range of values. The data
type of a specified value must match the data type of the corresponding components.
Table 4- 21 Elements of the DTL structure
Byte Component Data type Value range
0
1 Year UINT 1970 to 2554
2 Month USINT 1 to 12
3 Day USINT 1 to 31
4 Weekday
1
USINT 1(Sunday) to 7(Saturday)
1
5 Hour USINT 0 to 23
6 Minute USINT 0 to 59
7 Second USINT 0 to 59
8
9
10
11 Nanoseconds UDINT 0 to 999 999 999
1
The weekday is not considered in the value entry.
Table 4- 22 Character and String data types
Data type Size Range Constant Entry Examples
Char 8 bits ASCII character codes: 16#00 to 16#FF 'A', 't', '@'
String n+ 2 bytes n = (0 to 254 character bytes) 'ABC'
Char
Char data occupies one byte in memory and stores a single character coded in ASCII
format. The editor syntax uses a single quote character before and after the ASCII character.
Visible characters and control characters can be used. A table of valid control characters is
shown in the description of the String data type.