Epson S1D13705 technical manual 320x240 Single Panel For Split Screen

Epson Research and Development	Page 31
Vancouver Design Center

5.3 Split Screen

Occasionally the need arises to display two different but related images. Take, for example, a game where the main play area requires rapid updates and game status, displayed at the bottom of the screen, requires infrequent updates.

The Split Screen feature of the S1D13705 allows a programmer to setup a display in such a manor. When correctly configured the programmer has only to update the main area on a regular basis. Occasionally, as the need arises, the secondary area is updated.

The figure below illustrates how a 320x240 panel may be configured to have one image displaying from scan line 0 to scan line 199 and image 2 displaying from scan line 200 to scan line 239. Although this example picks specific values, the split between image 1 and image 2 may occur at any line of the display.

Scan Line 0

...

Scan Line 199

Scan Line 200

...

Scan Line 239

Image 1

Image 2

Screen 1 Vertical Size Registers = 199 lines

Figure 5-2: 320x240 Single Panel For Split Screen

In split screen operation “Image 1" is taken from the display memory location pointed to by the Screen 1 Start Address registers and is always located at the top of the screen. “Image 2" is taken from the display memory location pointed to by the Screen 2 Start Address registers. The line where “Image 1" end and “Image 2" begins is determined by the Screen 1 Vertical Size register.

Programming Notes and Examples	S1D13705
Issue Date: 02/01/22	X27A-G-002-03