Festo CPX-FB13, Manual

Page: 31 / 63

4 Commissioning
Festo – P.BE-CPX-CTEL-EN – 1411a – English 31
Assignment in the example with automatic configuration
Inputs (8 bytes):
Device Device address Input address CTEL
I-port 2 (1 byte) Byte 0 Byte 0
I-port 4 (2 bytes)
Byte 0 Byte 1
Byte 1 Byte 2
unused
– Byte 3
– Byte 4
– Byte 5
– Byte 6
– Byte 7
Legend: white = assigned; grey = unused
Outputs (8 bytes):
Device Device address Output address CTEL
I-port 1 (2 bytes)
Byte 0 Byte 0
Byte 1 Byte 1
I-port 3 (4 bytes)
Byte 0 Byte 2
Byte 1 Byte 3
Byte 2 Byte 4
Byte 3 Byte 5
unused
– Byte 6
– Byte 7
Legend: white = assigned; grey = unused
Unused bytes are filled with 0.
Through the possibility of automatic I/O configuration and exact-byte issuing of an indi­
vidual I/O length to each I-port, assignment of unused address space can be considerably
reduced compared to the manual configuration.
In the example, the assigned address space in the automatic configuration is 8 bytes I/8 bytes O
(12.5 % of the entire address space in the CPX system). To use the same devices in the manual config­
uration, 16 bytes I/16 bytes O are needed (25 % of the total address space in the CPX system).