ID-E270-011GB
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The LCD is connected (mechanically and electrically) with the PSC-49 central controller board located
on the control panel door.
5.3. PSC-49 CENTRAL CONTROLLER MODULE
The central controller module is equipped with two independent microprocessor circuits (µP1 and
µP2) which ensure mutual supervision and unfailing control panel operation. Each circuit has an
independent set of ROM memory (in a separate MP-49 memory module), RAM operating memory
and SETUP configuration memory (set of data defining the hardware environment and system
operation organisation). In normal operating conditions, the whole control panel operation is
managed by the first microprocessor circuit (µP1) – the active microprocessor. In case this circuit
fails, the entire control panel operation is monitored by the other (redundant) microprocessor circuit
(µP2). In this condition, the µP2 is the active circuit.
The circuits that execute the central panel communication bus for information exchange and other
modules (MSL-1M-42, PPW-42 and MZ-4212) controlling, are also located in the module.
The PSC-43 module is equipped with its own 3 V DC and 5 V DC converters to supply its own and
external electronic circuits.
5.3.1 Module signalling and handling elements
Illuminating diodes indicating the service conditions of the module operation are provided on the left
internal edge of the PSC-49 module.
At the back, two miniature push buttons marked as Reset µP1 and Reset µP2 are located below the
MP-49 module. They are used to restart a relevant µP1 or µP2 microprocessor (with short push
button pressing).
The SW1 switch is located in the centre of the module. It is a set of 8 keys (K1 ÷ K8) to change the
hardware and software setup of the control panel. The SW1 switch keys functions are described in
table 5.1.
Table 5.1
SW1 Key Position
Function
K1
ON
After an active microprocessor restart, the control panel standard configuration
loading
K2
ON
After an active microprocessor restart, the control panel operation data actuation
K3
ON
After an active microprocessor restart, loading standard access codes at the 2
nd
,
3
rd
and 4
th
levels
K4
ON
Switching on service diodes located on PSC-49 module
K5
Unused
K6
ON
Permission to reset SYSTEM FAULT – the reset is performer after an active μP1 or
μP2 microprocessor reset
K7
ON
OFF
If the K8 key in in the ON position:
- extortion of μP2 operation as the active microprocessor
- extortion of μP1 operation as the active microprocessor (e.g. in the system fault
condition)
K8
ON
Permission for ‘manual’ extortion of active microprocessor operation (using the
K7 key)
