Table of Contents
Advertisement
4. OPERATING AND PROGRAMMING THE SM40 SURVEILLANCE CENTRE
4.1
Central Processor Card - CPC
Eurocard 10 x 22 cm with an 'a b' connector (2 x 32). A microprocessor which can scan over 4000
monitoring devices, and activate more than 100 relays, via the communication line.
At the heart of the SM40 Surveillance Centre is the Central Processor Card (CPC). Capable of sequentially
scanning 4096 monitoring devices; activating 64 SSC solid state relays, and 40 CRC relay sets; and sending
error information to a display, external computer, or printer; this is a powerful piece of equipment. It
provides a system of this type with a great amount of possibilities.
A Display & Keyboard mounted in the rack unit's front panel, is used to display the scanning status and any
detected errors, and also to carry out the user programming.
When programming is complete the CPC returns to its normal scanning mode and, until a secret password
is entered, the keyboard has no influence on the processor.
The basic functions of the Central Processor Card are as follows:
SCANNING of Amplifier Surveillance Boards (ASB's) and/or Loudspeaker Surveillance Boards (LSB's).
This is done by sequentially sending 15V power to each of the 8 Test Lines of the Surveillance Switch Cards
(SSC's) in turn, then sending communications data to each board in each line sequentially.
Translating the error data received from the ASB's and LSB's, along with external sensing devices, and
relaying this information to the display, or via the RS232 port, to a printer or external computer.
ACTIVATING of relays, to switch on external warning devices (lamps, buzzers, paging units, etc.) via
Control Relay Cards (CRC's).
CHECKING of system hardware. The processor acts as a "watchdog", continuously patrolling the SM40
Surveillance Centre hardware to check for errors, malfunctions or disconnections. If a problem exists,
information, stating which card is faulty, is relayed to the display or printer.
An automatic restore function is also incorporated, so that when an internal error occurs, the system will not
hang-up, and when an error is rectified no manual system reset is required.
REAL TIME CLOCK is built into the unit, and (in the program's 'Enable Print' mode) is displayed on the
LCD, giving date, hours and minutes. When an error occurs, the current time and date are transmitted to
the printer. Synchronisation is via A17 on Surveillance Switch Cards No.1.
SERIAL INTERFACE. The standard RS232 serial interface connector mounted on a bracket on the frame,
and wired to the CPC, allows the system to communicate with a wide variety of personal, mini, and main-
frame computers as well as direct to serial printers.
The communication has 8 data bits, and the baud-rate is selectable between 300, 1200, 2400, 4800 and
9600 baud.
This, and the other I/O port parameters, such as number of Stop Bits, and Parity can be set in the installer
programming menu.
SM40's standard default parameters are:
2400 baud, 8 data bits, 1 stop bit, even parity.
A yellow LED, mounted on the front edge of the card indicates that the CPC is in communication with the
rest of the SM40 Surveillance Centre, and 1 green LED indicates that adequate supply voltage is present.
The CPC has additional driver stages for the communication lines of 5 of the Extension Frames used to
expand the Surveillance Basic System.
4
11
Advertisement
Table of Contents
