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Epson Research and Development
Vancouver Design Center
9 SwivelView™
Most computer displays operate in landscape mode. In landscape mode the display is wider
than it is high. For example, a standard display size of 640x480 is 640 pixels wide and 480
pixels wide.
SwivelView rotates the display image clockwise in ninety degree increments, possibly
resulting in a display that is higher than it is wide. Rotating the image on a 640x480 display
by 90 or 270 degrees yields a display that is now 480 pixels wide and 640 pixels high.
SwivelView also works with panels that are designed with a "portrait" orientation. In this
case, when SwivelView 0° is selected, the panel will be in a “portrait” orientation. A
selection of SwivelView 90° or SwivelView 270° rotates to a landscape orientation.
9.1 S1D13506 SwivelView
The S1D13506 provides hardware support for SwivelView in 8, 15 and 16 bpp color depths
on LCD panels. SwivelView is not supported on CRT or TV displays.
Certain conditions must be considered when SwivelView is enabled.
• The virtual display offset (scan line) must be set to 1024 pixels (1024 bytes in 8 bpp,
2048 bytes in 15/16 bpp) when SwivelView Enable Bit 0 is set to 1.
• The display start address is calculated differently when SwivelView is enabled.
• Calculations that would result in panning in landscape mode, may result in scrolling
when SwivelView is enabled and vice-versa.
9.2 Registers
REG[01FCh] Display Mode Register
SwivelView
Enable Bit 0
Display Mode Display Mode Display Mode
Select Bit 2 Select Bit 1 Select Bit 0
n/a
n/a
n/a
n/a
n/a
REG[040h] LCD Display Mode Register
LCD Display
Blank
SwivelView
Enable Bit 1
Bit-Per-Pixel Bit-Per-Pixel Bit-Per-Pixel
Select Bit 2 Select Bit 1 Select Bit 0
n/a
n/a
The SwivelView modes are enabled using a combination of 2 enable bits - SwivelView
Enable Bit 0 (REG[1FCh]) and SwivelView Enable Bit 1 (REG[040h]). The combinations
of these bits provide the following rotations.
S1D13506
X25B-G-003-03
Programming Notes and Examples
Issue Date: 01/02/06
EPSON [ EPSON COMPANY ]
