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FIG3-6 On-Screen Display
ViewSonic Corporation
22
Confidential
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Do
Not Copy
V
E510+-1
On-Screen Display
Mascot V OSD display support 256 different fonts at size of 12x18, 256 fonts contain
128 fixed fonts that stored in internal ROM, other 128 programmable fonts stored in
internal SRAM. OSD also supports Overlay port interface and color look-up table with
4 color indices from external OSD and Opaque, Translucence, Transparent display.
Diagram listed below is the concept of how OSD retrieves and displays OSD Font.
See FIG3-6.
When OSD key is been pressed, firmware will detect the change and perform the
procedure, once firmware start “drawing” OSD, it will program the OSD code and
attribute to the OSD SRAM. Chip will look-up the OSD code then retrieve the character
font data that corresponding to the code and then display the character on LCD panel.
There are 320 memory spaces from 0 to 319 in SRAM. It is sequentially mapped to the
OSD frame started from the upper-right corner and goes horizontally to the upper-left
corner and then move to 2
nd
row etc. Ended at left-bottom corner. OSD frame are divided
by 0
Д
9 in row, total is 32x10=320 characters.
Diagram listed below is the concept of how 24bit RGB OSD character been composed,
see FIG3-7 OSD Display Flow Chart. Each OSD character font data that read out from
ROM table will use the 4-bit foreground and 4-bit background color to determine its color.
Use this 4-bit color index to look-up the palette and select related 15bit RGB foreground
and background color. And added 3bit 0 to each R, G, and B channel then generate 24it
RGB color for the OSD character.
Summary of Contents for VE510+-1
Page 10: ...3 Disassembly Assembly Instructions ViewSonic Corporation 7 Confidential Do Not Copy VE510 1...
Page 11: ...ViewSonic Corporation 8 Confidential Do Not Copy VE510 1...
Page 27: ...FIG3 8 Mascot function block ViewSonic Corporation 24 Confidential Do Not Copy VE510 1...
Page 30: ...FIG4 2 MPU Control Block ViewSonic Corporation 27 Confidential Do Not Copy VE510 1...
Page 43: ...ViewSonic Corporation ViewSonic Corporation 40 Confidential Do Not Copy VE510 1...
Page 44: ...ViewSonic Corporation ViewSonic Corporation 41 Confidential Do Not Copy VE510 1...
Page 45: ...ViewSonic Corporation ViewSonic Corporation 42 Confidential Do Not Copy VE510 1...
Page 46: ...8 PCB Layout ViewSonic Corporation 43 Confidential Do Not Copy VE510 1...
Page 47: ...ViewSonic Corporation 44 Confidential Do Not Copy VE510 1...