Siemens SIMATIC OEM PP32, Руководство по эксплуатации оборудования

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3-3
OEM Push Button Panel Equipment Manual
Release 08/98
The following figure illustrates the structure of the data block or marker byte in
the PLC to which the Push Button Panel is assigned in an example of an MPI
connection. It is important to note that two control bits are assigned to each
LED and each output, and the bits are distributed on successive bytes. The
combination of these bits determines the appearance of the LED or display
element.
Digital inputs 1–8
Digital inputs 9–16
Structure of the data in the PLC: Element assignment:
0
Keys 1–8
Keys 9–16
Keys 17–24
Keys 25–32
Key 1
LED 1
Digital
output 10
Digital
input 5
Key 24
LED 24
0
1
8
16
7
10
17
Bit Assignment:
LEDs 1–8
LEDs 9–16
LEDs 17–24
LEDs 25–32
Digital outputs 1–8
Digital outputs 9–16
Byte
}
}
}
}
}
}
1
8
16
Digital
inputs
1–16
(DI)
Digital
outputs
1–16
(DO)
Figure 3-5 Control bits for OEM PP32 and
OEM PP32/OP17
When a PROFIBUS-DP connection is used, the data blocks represented in
Figure 3-5 can be assigned separate starting addresses corresponding to the
inputs/outputs.
Control Bit Assignment