SED1374 Datasheet, PDF (133/420 Pages) Epson Company – SED1374 Embedded Memory Color LCD Controller

Epson Research and Development
Vancouver Design Center
Page 37
physical
memory
start
address
The following figures show how the programmer sees a 240x320 image and how the image
is displayed. The application image is written to the SED1374 in the following sense:
A–B–C–D. The display is refreshed by the SED1374 in the following sense: B-D-A-C.
256
A
B
E
SwivelView
window
C
D
240
image seen by programmer
= image in display buffer
display
start
address
320
image refreshed by SED1374
Figure 7-1: Relationship Between The Screen Image and the Image Refreshed by SED1374
7.3 Alternate SwivelView Mode
Alternate SwivelView Mode may be used when the virtual image size of Default
SwivelView Mode cannot be contained in the 40k Byte integrated frame buffer. For
example, when the panel size is 240x160 and the display mode is 8 bit-per-pixel the
minimum virtual image size for Default SwivelView Mode would be 240x256 which
requires 60K bytes. Alternate SwivelView Mode requires a panel size of only 240x160
which needs only 38,400 bytes.
Alternate SwivelView Mode requires the memory clock (MCLK) to be at least twice the
frequency of the pixel clock (PCLK), i.e. MCLK ≥ 2 x PCLK.
Because of this, the power consumption in Alternate SwivelView Mode is higher than in
Default SwivelView Mode.
The following figure shows how the programmer sees a 240x160 image and how the image
is being displayed. The application image is written to the SED1374 in the following sense:
A–B–C–D. The display is refreshed by the SED1374 in the following sense: B-D-A-C.
Programming Notes and Examples
Issue Date: 99/04/27
SED1374
X26A-G-002-02