Sharp LC-28HM2U Service Manual page 13

Æ Description of PC I/F unit
Simplified block diagram
Microprocessor
Sync signal selector
EEPROM
Flash ROM
Memory
External device control
PC I/F unit has the following functions.
(1) Selection of analog video input signal of 2 systems
(2) Enlargement, reduction (including wide angle processing) and complement of video signals
(3) Production of signals required for the display in the steps to follow
(4) Synthesis of OSD (channel call, menu, etc)
(5) Encoding of the prepared video signal and timing signal for output
(6) Control of external devices (video adjustment, video source selection, power supply, etc) (Same as ordinary
microprocessor)
(7) Storage of information such as adjustment data
Program data and OSD data are stored in the flash ROM and can be rewritten externally.
Video line input (1Vp-p)
Sync
Video
signal
signal
3ch AD converter
G/A group
» Frequency detection (PC line)
» Video enlarge, reduce and
complement
» EN signal and Dotclk
production
» OSD synthesis
PC input (0.7Vp-p)
Clamp/bias/gain adjustment
Video signal
and
timing signal
13
LC-28HM2
AN-28SP2
Encoded
signal
Encoder IC