2-3
The Master Controller PCB assembly supervises panel operations and controls
the front panel user interface. The Master Controller communicates with panel
PCB subassemblies via a +28V signal level communications interface.
Peripheral PCB assemblies are optically coupled to this communications
interface.
Based upon the information in the configuration flash chip (U8) the Master
Controller communicates with peripheral interface cards and directs system
monitor point supervision and signal circuit control. The Master Cont5V
and +28V A-tap power originates on the Power I/O Interface and is daisy
chained through the Standard Slave card.
The Master Controller:
•
Includes main 80196 microprocessor and memory
•
Processes data from all other 4020 sub-assemblies
•
Controls operator keyboard, piezo alarm and display interface
•
Provides a programmer interface for downloading configuration changes
•
Includes city circuit interface and contains a dry contact trouble circuit
•
Contains communications circuitry to Slave cards and LCD Annunciators
Continued on next page
4020 Master Controller
Description
Master Controller Functions
