Filter
Top Products
Page 12 Epson Research and Development
Vancouver Design Center
S1D13708 Programming Notes and Examples
X39A-G-003-01 Issue Date: 01/11/20
ADVANCE
D
IN
F
ORMATION
Subje
ct to C
ha
nge
4 Memory Models
The S1D13708 contains a display buffer of 80K bytes and supports color depths of 1, 2, 4,
8, and 16 bit-per-pixel. For each color depth, the data format is packed pixel.
Packed pixel data may be envisioned as a stream of pixels. In this stream, pixels are packed
adjacent to each other. If a pixel requires four bits, then it is located in the four most signif-
icant bits of a byte. The pixel to the immediate right on the display occupies the lower four
bits of the same byte. The next two pixels to the immediate right are located in the following
byte, etc.
4.1 Memory Organization for One Bit-per-pixel (2 Colors/Gray Shades)
Figure 4-1: Pixel Storage for 1 Bpp in One Byte of Display Buffer
At a color depth of 1 bpp, each byte of display buffer contains eight adjacent pixels. Setting
or resetting any pixel requires reading the entire byte, masking out the unchanged bits and
setting the appropriate bits to 1.
One bit pixels provide 2 gray shades/color possibilities. For monochrome panels the gray
shades are generated by indexing into the first two elements of the green component of the
Look-Up Table (LUT). For color panels the 2 colors are derived by indexing into the first
2 positions of the LUT.
4.2 Memory Organization for Two Bit-per-pixel (4 Colors/Gray Shades)
Figure 4-2: Pixel Storage for 2 Bpp in One Byte of Display Buffer
At a color depth of 2 bpp, each byte of display buffer contains four adjacent pixels. Setting
or resetting any pixel requires reading the entire byte, masking out the unchanged bits and
setting the appropriate bits to 1.
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Pixel 0 Pixel 1 Pixel 2 Pixel 3 Pixel 4 Pixel 5 Pixel 6 Pixel 7
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Pixel 0
Bits 1-0
Pixel 1
Bits 1-0
Pixel 2
Bits 1-0
Pixel 3
Bits 1-0