S1D13505 Epson Electronics America, Inc., S1D13505 Datasheet - Page 142

• Manufacturer Part Number: S1D13505
• Description: LCD Controller
• Manufacturer: Epson Electronics America, Inc.

Page 136
13.2 Image Manipulation in SwivelView
S1D13505
X23A-A-001-14
Display Start Address
It can be seen from Figure 13-1 that the top left pixel of the display is not at the top left corner of the
virtual image, i.e. it is non-zero. The Display Start Address register must be set accordingly:
Memory Address Offset
The Memory Address Offset register must be set for a 1024 pixel offset:
Horizontal Panning
Horizontal panning is achieved by changing the start address. Panning of the portrait window to the
right by 1 pixel is achieved by adding 1024 pixels to the Display Start Address register (or
subtracting if panning to the left).
• Panning to right by 1 pixel: add current start address by 1024 (16 bpp mode) or 512 (8 bpp
• Panning to left by 1 pixel: subtract current start address by 1024 (16 bpp mode) or 512 (8 bpp
How far the portrait window can be panned to the right is limited not only by 1024 pixels but also
by the amount of physical memory installed.
Vertical Scrolling
Vertical scrolling is achieved by changing the Display Start Address register and/or changing the
Pixel Panning register.
• Increment/decrement Display Start Address register in 8 bpp mode: scroll down/up by 2 lines.
• Increment/decrement Display Start Address register in 16 bpp mode: scroll down/up by 1 line.
• Increment/decrement Pixel Panning register in 8 bpp or 16 bpp mode: scroll down/up by 1 line.
mode).
mode).
Display Start Address (words)
Memory Address Offset (words)
=(1024 - W)
=(1024 - W) / 2
=1024
=512
for 16 bpp mode
for 8 bpp mode
for 16 bpp mode
for 8 bpp mode
Epson Research and Development
Hardware Functional Specification
Vancouver Design Center
Issue Date: 01/02/02