ST950S Plus+ Installation and Commissioning Manual
The CIC is fitted with a metallic cover to provide a degree of protection from accidental contact.
However, there are no hazardous voltages present on the PCB.
Figure 29. CTB Terminations
3.15.2. CIC/CTB Interfaces: Serial Phase Bus (SPB)
The CIC/CTB has two SPB interfaces, SPB In and SPB Out. The SPB In connection for the first CIC/
CTB in the system connects to the ST950 CPU. The SPB Out connects to the next CIC/CTB in the
system via its SPB-IN connector.
Over this interface the ST950 CPU can obtain lamp states as well as inventory and fault information
from the CIC and the Nodes.
The scheme is arranged such that messages sent by the ST950 CPU are routed to, and seen by, all
devices on the bus but replies from downstream devices are directly routed to the ST950 CPU without
being seen by other devices on the bus.
3.15.3. CIC/CTB Interfaces: GSPI Bus
The CIC/CTB has two GSPI interfaces, GSPI In and GSPI Out. The GSPI In connection for the first
CIC/CTB in the system connects to the ST950 EFC. The GSPI Out connects to the next CIC/CTB in
the system via its GSPI In connector. The last CIC/CTB in the system may, via its GSPI Out, connect to
optional Serial I/O Cards. Refer to section
.
Over this interface the ST950 CPU can obtain I/O input states as well as inventory and fault information
from the CIC and the Nodes.
The communication scheme is arranged such that messages sent by the ST950 CPU are routed to,
and seen by, all devices on the bus but replies from downstream devices are directly routed to the
ST950 CPU without being seen by other devices on the bus.
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