Epson Research and Development

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Vancouver Design Center

 

 

 

12 SwivelView™

Many of todays applications use the LCD panel in a portrait orientation. In this case it becomes necessary to “rotate” the displayed image by 90°. This rotation can be done by software at the expense of performance or, it can be done by the S1D13705 hardware with no CPU penalty.

There are two SwivelView modes: Default SwivelView Mode and Alternate SwivelView Mode.

12.1 Default SwivelView Mode

Default SwivelView Mode requires the SwivelView image width be a power of two, e.g. a 240-line panel requires a minimum virtual image width of 256. This mode should be used whenever the required virtual image can be contained within the integrated display buffer (i.e. virtual image size 80K bytes), as it consumes less power than the Alternate SwivelView Mode.

For example, the panel size is 320x240 and the display mode is 8 bit-per-pixel. The virtual image size is 320x256 which can be contained within the 80K Byte display buffer.

Default SwivelView Mode also requires Memory Clock (MCLK) Pixel Clock (PCLK).

The following figure shows how the programmer sees a 240x320 image and how the image is displayed. The application image is written to the S1D13705 in the following sense: A–B–C–D. The display is refreshed by the S1D13705 in the following sense: B-D-A-C.

physical memory start address

320

256

A

B

E

SwivelView window

C D

240

image seen by programmer = image in display buffer

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

E

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

display

B

 

 

 

 

SwivelView window

 

 

 

 

 

D

 

 

240

 

 

 

 

 

 

 

 

 

 

 

A

 

 

 

 

 

 

 

 

 

C

 

 

start

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

address

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

320

 

 

 

 

 

 

 

 

 

 

 

image refreshed by S1D13705

256

Figure 12-1: Relationship Between The Screen Image and the Image Refreshed by S1D13705 in Default Mode

Hardware Functional Specification

S1D13705

Issue Date: 02/02/01

X27A-A-001-10

Page 83
Image 83
Epson S1D13705 technical manual Default SwivelView Mode