Siemens ST750 General Handbook page 19

• CPU – A new variant of the CPU board is required for operation in the ST750.
Although the ST700 and ST750 CPU Cards look very similar, the ST750 requires
at least 512KB of RAM and only 256KB is fitted to most ST700 CPU Cards.
The ST750 requires a CPU board with a /003 part number suffix for
Note
UK applications or /007 for Non-UK applications. Earlier i.e. ST700
CPU boards can NOT be used in an ST750
• PHP – PB801 and the ST750 require PB817 issue 5 or later; PB800 and the
ST700 can use PB817 issue 3 or later (which includes PB817 issue 5).
• IO – PB801 firmware on the ST750 controller continues to use the I/O built in to
the CPU Card, with the option of adding one ST800 style Expansion I/O Board.
• SDE – Integral SDE/SA is still used, using the I/O on the CPU Card. The
SDE/SA Card on the Extended System Bus is not supported by the firmware.
• Config – The standard stand-alone pedestrian configurations have changed. A
list of these can be found in the IC4 ReadMe file (v11) and in this document
(section 5.15). A list of the significant changes between a new ST750 standard
configuration and its original ST700 configuration is included in its Special
Instructions (from issue 2).
• Kerbsides – As required by TR2500A in the UK, pushbuttons now insert a
latched demand if they are pressed while their associated kerbside detector is
inactive. If its associated kerbside detector is active, an unlatched demand is
inserted (which is cancelled when all the kerbside detectors for the phase go
inactive).
• DFM – DFM Faults on the individual I/O lines no longer appear in the Fault Log
Data (FLD) and should be interrogated using the DSF handset command, which
also displays the I/O Line Number and IC4 Name as well as indicating whether
the input failed active (1) or inactive (0).
• DFM – The 'Reset DFM' facility (RDF=1 for example) will now clear the DFM
fault flag (FLF12) and extinguish the System Error LED.
• Priority – The 'Automatic Reset' option of the Priority DFM Facility (PDR) has
been improved so that a number of activations can be specified; the N'th
activation is allowed and the fault is automatically cleared.
• Handset – The handset now auto-detects Eight Data Bits with No Parity Bit (8N)
as well as continuing to support Seven Data Bits with an Even Parity Bit (7E) and
1200, 9600 and 19200 bps.
• Handset – Level 2 (PME) and Level 3 (Pushbutton) Access Timeout Periods are
restarted if Level 2 or 3 data is changed (including RFL=1 for example) or the
PME access code is re-entered.
• Config – The new CID handset command displays the firmware version (as
entered on the IC4 Admin Screen) 'desired' by the configuration currently
running a controller. The EM number and issue of the configuration is still visible
using the CIC handset command.
667/HB/33750/000 Page 19
ST750 G H
ENERAL ANDBOOK
Issue 6