User's Manual

SBS-900 Shore Based Radar Systems
Chapter 10: Corrective maintenance
KH-1602-2 issue 1: Standard SBS900 Systems Operator & Maintenance Handbook
Page 212 of 240
10.8.13 VDR-A121-3 status and control PCB
The Status and Control PCB Assembly (Front panel)
provides indication of the unit status by means of an
LCD display and a set of LEDs, and provides control
of the unit functions by means of four pushbutton
switches.
The unit is interfaced via a bi-directional RS232 serial
data link on PL1 to SK3 on the backplane.
The four switches are momentary action pushbutton switches. The lower right switch also contains an
integral LED indication, which may or may not be used depending on the requirements of the parent
equipment.
When a switch is pressed the interface to the microprocessor is pulled down to ground and this is
detected by the microprocessor. The switch functions and LED display are determined by the
configuration software, not by the on-board software.
LEDs, links and test points
LEDs
D
1
Red LED - Lit when unit is being programmed (Kelvin Hughes use only)
D
2
Red LED
Front panel LEDs: The LED status depends on system activity.
D3
Green LED
D4
Yellow LED
Note: PL4 is used for programming the PCB during manufacture and must not be used for any other purpose. Caution:
Unauthorised use of this port can rendering the PCB defective.
Power
The board uses the +12V rail direct from the backplane which is received on PL1 pins 1 & 2. (+12V)
+12V DC from PL1 pins 1 and 2.
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Software
The status & control PCB runs ZM-2010 software which has no user configurable parameters.