ABB Advant Controller 80 User Manual page 73

Control of the
Special I/O Link
AC 80 (NCB Board)
CH3
CH0
CH1
CH2
NBIO-31
DEVICE 1
(node 1)
AC 80 User's Manual
The Special I/O link is a DDCS-protocol fibre optic ring that can contain
up to eight I/O devices. The sequence of the devices determines the
node numbers as shown below.
NPCT-01 NBIO-21
DEVICE 2 DEVICE 3
(node 2) (node 3)
Figure 4-32 The Special I/O link.
The terminal values of the I/O devices are accessed by the application
program through PC and DB elements. Also note that the system
software package of the AC 80 includes type circuits for handling
Special I/O devices. For detailed information, refer to the AC 80
PC Elements Reference Manual.
NDSC-01
DEVICE 4 DEVICE 5
(node 4) (node 5)
DEVICE 6 DEVICE 7
(node 6) (node 7)
DEVICE 8
(node 8)
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