Filter
Top Products
Epson Research and Development Page 133
Vancouver Design Center
Hardware Functional Specification S1D13708
Issue Date: 02/03/07 X39A-A-001-02
8.3.5 Display Mode Registers
bit 7 Display Blank
When this bit = 0, the LCD display pipeline is enabled.
When this bit = 1, the LCD display pipeline is disabled and all LCD data outputs are
forced to zero (i.e., the screen is blanked).
bit 6 Dithering Disable
When this bit = 0, dithering on the passive LCD panel is enabled, allowing a maximum of
256K colors (2
18
) or 64 gray shades in 1/2/4/8 bpp mode. In 16bpp mode, only 64K colors
(2
16
) is allowed because the LUT is bypassed.
When this bit = 1, dithering on the passive LCD panel is disabled, allowing a maximum of
4096 colors (2
12
) or 16 gray shades.
Note
For a summary of the results of dithering for each color depth, see Table 8-9: “LCD Bit-
per-pixel Selection,” on page 135.
All passive STN color panels are controlled using 3 bits for each pixel (RGB) for a total of
8 possible colors. LCD controllers use a combination of Frame Rate Modulation (FRM)
and dithering to achieve more than 8 colors per pixel. FRM can achieve 16 shades of color
for each RGB component resulting in a total of 4096 possible colors (16x16x16). Dithering
uses a 4 pixel square formation and applies a set of 4 hard-coded patterns for each of the 16
shades of color. This expands the original 16 shades of color from the FRM logic to 64
shades per RGB component which results in 256K colors per pixel (64x64x64).
For the S1D13708, 16 bpp is arranged as 5-6-5 RGB. In this mode, when dithering is
enabled, the LUT is bypassed and the original 16-bit data is used as a pointer into the 64
shades per color in the following manner.
(5-6-5 RGB) 32 possible Red, 64 possible Green, 32 possible Blue
This combination of FRM and dithering results in 256K colors/pixel, however, the 16 bpp
limitation of the S1D13708 limits this to 64K colors/pixel.
Display Mode Register
REG[70h] Read/Write
Display Blank
Dithering
Disable
Hardware
Video Invert
Enable
Software
Video Invert
n/a Bit-per-pixel Select Bits 2-0
76543210