JVC 330 Service Manual page 72

Chapter 2—Functional Descriptions
General Functional Description
The system controller board receives external commands, interprets those
commands, and issues internal commands to control the operation of the arc lamp,
light valves, raster generation, video signal amplifiers, and other components
necessary for projector operation.
The SCB receives commands from the outside world via the IR or RS232
interface. Output communication is accomplished via the RS232, the dot matrix
display, and the CRT display.
Control of raster generation by the SCB is limited to primarily controlling
geometric and convergence correction while most other raster functions are under
local hardware control.
Video signal control involves choosing which video input to use, whether or not
to insert overlays, and setting gain and offset values.
The SCB also takes in information on raster and video status from other circuit
boards and generates control signals and displays based on that information.
2-60 Model 330. 340SC, and 370SC Service Manual