Epson Research and Development
Page 207
Vancouver Design Center
15.3.2 Limitations
The following limitations apply to 180° SwivelView™:
• Hardware Cursor and Ink Layer images are not rotated – software rotation must be used.
• CRT/TV mode is not supported.
• 180° SwivelView™ does not support all BitBlts.
15.4 270° SwivelView™
270° SwivelView™ is a combination of 90° SwivelView™ and 180° SwivelView™. The
image stored in the display buffer is 90° rotated, and the image is further 180° rotated
during screen refresh, resulting in a 270° rotated display image. The user must use a 1024
× 1024 pixel virtual window as in 90° SwivelView™. See Figure 15-1: “Relationship
Between Screen Image and 90° Rotated Image in the Display Buffer,” on page 201.
15.4.1 Register Programming
Enabling 90° Rotation on CPU Read/Write to Display Buffer
Set SwivelView™ Enable bit 0 to 1. All CPU access to the display buffer is translated to
provide 90° clockwise rotation of the display image.
Reverse Display Buffer Fetching Address Direction
Set SwivelView™ Enable bit 1 to 1. During screen refresh, the direction of the address for
display buffer fetching is reversed. This setting does not affect CPU to display buffer access
in any way.
Memory Address Offset
The LCD Memory Address Offset register (REG[046h], REG[047h]) must be set for a
1024 pixel offset.
LCD Memory Address Offset (words)
= 1024
= 512
for 15/16 bpp mode
for 8 bpp mode
Hardware Functional Specification
Issue Date: 01/02/06
S1D13506
X25B-A-001-10
EPSON [ EPSON COMPANY ]
