Page 14 Epson Research and Development
Vancouver Design Center
S1D13705 Programming Notes and Examples
X27A-G-002-03 Issue Date: 02/01/22
3.4 Eight Bit-Per-Pixel (256 Colors)
In eight bit-per-pixel mode one byte of display buffer represents one pixel on the display.
At this color depth the read-modify-write cycles, required by the lessor pixel depths, are
eliminated.
When using a color panel, each byte of display memory acts as and index to one element
of the LUT. The displayed color is arrived at by taking the display memory value as an
index into the LUT.
Eight bit per pixel is not supported for monochrome display modes. The reason is that eac h
element of the LUT supports a 4-bit (sixteen value) level for red, green and blue. In
monochrome display modes on the green value is used to set the gray intensity. Thus we
have sixteen possible grey values but, because of the color
.
Figure 3-4: Pixel Storage for 8 Bpp (256 Colors) in One Byte of Display Buffer
Bit 7Bit 6Bit 5Bit 4Bit 3Bit 2Bit 1Bit 0
Red bit 2 Red bit 1 Red bit 0 Green bit 2 Green bit 1 Green bit 0 Blue bit 1 Blue bit 0