Memory Models; Display Buffer Location; Memory Organization For One Bit-Per-Pixel (2 Colors/Gray Shades) - Epson S1D13706 Technical Manual

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3 Memory Models

3.1 Display Buffer Location

3.2 Memory Organization for One Bit-per-pixel (2 Colors/Gray Shades)

Bit 7 Bit 6
Pixel 0 Pixel 1
S1D13706
X31B-G-003-03
The S1D13706 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.
The S1D13706 display buffer is 80K bytes of embedded SRAM. The display buffer is
memory mapped and is accessible directly by software. The memory block location
assigned to the S1D13706 display buffer varies with each individual hardware platform.
For further information on the display buffer, see the S1D13706 Hardware Functional
Specification, document number X31B-A-001-xx.
For further information on the S1D13706 Evaluation Board, see the S5U13706B00C
Evaluation Board Rev. 1.0 User Manual, document number X31B-G-004-xx.
Bit 5 Bit 4
Pixel 2 Pixel 3
Figure 3-1: 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.
Epson Research and Development
Bit 3 Bit 2
Pixel 4 Pixel 5
Vancouver Design Center
Bit 1 Bit 0
Pixel 6 Pixel 7
Programming Notes and Examples
Issue Date: 01/02/23