Festo CPX-CEC Series Manual page 45

Module and channel diagnosis
a[177] = 2#00000100
a[178] = 2#00000010
a[179] = 2#00000000
a[180] = 2#00000000
...
a[192] = 2#00000000
a[193] = 2#00000010
a[194] = 2#00000000
...
Bytes 1..4: Module diagnosis
Byte 1
Byte 2
Bytes 5..20: Channel diagnosis
Bytes 5..12
Bytes 13..20
Modular valve terminal with integrated controller CPX-CEC-...
System description table B/41
Number of the first faulty channel = 4 (=5th channel)
Module fault number
System description table B/41
8 input channels
8 output channels
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