Specifications

Mobility and Logistics, Traffic Solutions
Sopers Lane, Poole, Dorset, BH17 7ER
Security classification Unrestricted Page 73 of 83
Version 2 Status Released
Last Editor Harry Smyth Date 09/12/2014
Document Name Configuration Control Document No. 667/CC/45950/000
Copyright © Mobility 2014. All Rights Reserved. Mobility is a division of Siemens Plc
4.13 Serial I/O Cards
The Serial Input/Output (I/O) Kits do not form part of the Outercase selected from Table 4
and therefore should be ordered separately. Two types of I/O cards, remote from the CPU
Card, are available one with 4 outputs/16 inputs and one with 16 outputs/16 inputs. Four I/O
cards can be configured to the ST950. Figure 37 sets out stencil indications on the Terminal
Panel to aid positioning optimisation.
Figure 70 – Serial I/O Card
The I/O cards communicate with the CPU card via the RJ45 Cat5e, as a serial link. The
serial link communication protocol relies on addressing techniques to ensure the appropriate
information is delivered to the intended component. This means that the order in which the
components are connected to the fast serial link is not imperative to successful
communications. However, to maintain consistency of build sequence of connections set out
in Table 5 should be used.
As stated above, once connected into the serial link the CPU card indentifies the I/O by the
appropriate address. The address is set on the I/O card, shown Figure 70. Controller special
instructions will provide details on assigned inputs and outputs.
Serial Link
OUT
Serial Link
IN
Serial I/O
Address
Switch
Inputs Inputs
Outputs