3
Parameterisation
Festo – CPX-E-PB-EN – 2017-07 – English
23
3.2.8
Transfer input and output data – Data_Exchange
The cyclic data exchange takes place using the Data_Exchange function.
The output data for system CPX-E is sent as an octet string using this function. The string length depends on the
number of identifier bytes.
With the Data_Exchange function, system CPX-E expects the output data for the valves and electrical
outputs. The input data is sent to the DP master as an answer telegram.
The following table shows an overview of the user data (Data_Exchange) for the example Fig. 3.1.
Output data (Outp_Data)
Input data (Inp_Data)
No. Module type
Byte
Octet Bit Outlet
No. Module type
Octet Bit Input
2
CPX-E-8DO
0
1
0
x.0
0
CPX-E-PB
(status bits)
0
1
0
Diagnostic
message
1
x.1
1
…
…
…
7
x.7
7
3
CPX-E-8DO
1
2
0
y.0
1
CPX-E-16DI
1
2
0
t.0
1
y.1
1
t.1
…
…
…
…
7
y.7
7
t.7
5
CPX-E-4AO-U-I
2
3
0
z.0
2
3
0
u.0
1
z.1
1
u.1
…
…
…
…
7
z.7
7
u.7
3
4
0
(z+1).0
4
CPX-E-4AI-U-I
3
4
0
v.0
1
(z+1).1
1
v.1
…
…
…
…
7
(z+1).7
7
v.7
…
…
…
…
4
5
0
(v+1).0
9
10
0
(z+7).0
1
(v+1).1
1
(z+7).1
…
…
…
…
7
(v+1).7
7
(z+7).7
…
…
…
…
10
11
0
(v+7).0
1
(v+7).1
…
…
7
(v+7).7
1) Output byte
2) Address offset of master module: x, y, z
3) Input byte
4) Address offset of master module: t, u, v
Tab. 3.15