Siemens SINUMERIK 802C Manual page 58

Start-Up
4.3 Starting up the PLC
Compared with the S7–200 MicroWin basic system, please note the following:
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The PLC 802 Programming Tool is delievered in the English language version.
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The user program can only be programmed using ladder diagram.
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Only a subset of the S7–200 programming language is supported.
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The compilation of the user program is carried out either offline on a programming device
(PG)PC or semi–automatically when downloading into the control system.
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The project can be loaded into the control system (download).
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It is also possible to load the project from the control system (upload).
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Direct data addressing is not possible; therefore, no programming errors will rsult during
the operation.
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The data/process information must be managed by the user in accordance with the parti-
cular type.
Example:
Information 1
Information 2
User data
Byte 0
Byte 4
The user is not allowed to access both of these data at the same time; otherwise, the rele-
vant data access rules must be observed.
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Furthermore, the data direction in the memory model (alignment) and the data type must
be observed for all data.
Example:
Flag bit
Flag byte
Flag word
Flag double–word
Table 4-6 PLC data types permitted in the control system
Data Type Size
BOOL 1 bit
BYTE 1 byte
WORD 2 bytes
DWORD 4 bytes
(Double
Word)
REAL 4 bytes
PLC project
In any case, the PLC 802 Programming tool manages one project (logic operations, symbols
and comments). The download function is intended to store all important information of a pro-
ject in a control system.
4-58
T value DWord memory size
Override Byte memory size
DWord (Information 1)
Byte (Information 2)
MB0.1,MB3.5
MB0,MB1,MB2
MW0,MW2,MW4
MW3, MW5 ... are not permissible
MD0,MD4,MD8
MD1,MD2,MD3, MD5 ... are not permissible
Address Range for Logic Operations
Alignment
1 0, 1
1 00 ... FF
2 0000 ... FFFF
4 0000 0000 ... FFFF FFFF
4 –
(32–bit)
(8–bit)
Range for Arithmetical Opera-
tions
–
0 ... +255
–32 768 ... + 32 767
–2 147 483 648 ...
+2 147 483 647
$10 ... $10
–37 38
SINUMERIK 802C
6FC5 597–3AA20–0BP2 (01.02)