sed1355 ETC-unknow, sed1355 Datasheet - Page 142

• Manufacturer Part Number: sed1355
• Description: Sed1355 Embedded Ramdac Lcd/crt Controller
• Manufacturer: ETC-unknow

Page 136
13 SwivelView™
13.1 Concept
SED1355
X23A-A-001-11
C
A
window
portrait
H
Figure 13-1: Relationship Between The Screen Image and the Image Residing in the Display Buffer
image seen by programmer
D
B
1024 pixels
Note
Computer displays are refreshed in landscape – from left to right and top to bottom; computer images
are stored in the same manner. When a display is used in SwivelView it becomes necessary to rotate
the display buffer image by 90 . SwivelView rotates the image 90 clockwise as it is written to the
display buffer. This rotation is done in hardware and is transparent to the programmer for all display
buffer reads and writes.
SwivelView uses a 1024 1024 pixel virtual image. The following figures show how the
programmer sees the image and how the image is actually stored in the display buffer. The display
is refreshed in the following sense: C–A–D–B. The application image is written to the SED1355 in
the following sense: A–B–C–D. The SED1355 rotates and stores the application image in the
following sense: C–A–D–B, the same sense as display refresh.
The image must be written with a 1024 pixel offset between adjacent lines (e.g. 1024 bytes for
8 bpp mode or 2048 bytes for 16 bpp mode) and a display start address that is non-zero.
W
display
address
start
image in display buffer
1024 pixels
Epson Research and Development
Hardware Functional Specification
W
Vancouver Design Center
Issue Date: 99/05/18
H