Displaying A Single Image On A Dual Panel - Epson S1D13503 Series Technical Manual

EPSON

Displaying a Single Image on a Dual Panel

The following is the procedure to show a single image on a dual panel LCD. In this procedure the
single image is broken into two smaller images; the first half of the image is placed on the top panel
and the second half is placed on the bottom panel. For this example the S5U13503P00C is used with
a 4 gray shade 640 × 480 dual panel LCD; the Memory Interface is set to 16 bits to support 128K of
display memory.
1. Determine whether the Display Start Address Registers refer to bytes or words.
Since the Memory Interface is set to 16 bits, the Display Start Address Registers refer to words.
Note that when addresses refer to words, the image must be aligned in memory such that the
beginning is found on a word boundary (the least significant bit of the memory address must be
0).
2. Calculate the number of bytes per scan line.
Number of bytes per scan line
3. Determine the display memory location for the first half of the image.
For simplicity, assign the beginning of display memory as the starting address of the image's first
half (see Figure 5-7). For the S5U13503P00C, this address is D000:0000h, bank 0.
4. Program the Screen 1 Display Start Address Register to point to the beginning of the first half of
the image.
Since the first half is at the beginning of display memory, program the Screen 1 Display Start
Address Register to 0000h.
AUX[06h] = 00h
AUX[07h] = 00h
5. Determine the size of the image's first half.
Vertical size of first half of image
2-36
→
4 gray shades
→
2 bits per pixel
=
=
Screen 1 Display Start Address
Screen 2 Display Start Address
Figure 5-7 Memory Map for a Dual Panel Showing a Single Image
= Vertical size of panel 1
Number of scan lines in display
= ---------------------------------------------------------------------------------- -
Display width in pixels
Size =
--------------------------------------------------------- -
640
= --------- -
4
2 bits per pixel
4 pixels per byte
Pixels per scan line
-------------------------------------------------- - =
Pixels per byte
160 bytes per scan line
Display Memory
First Half of Image
Second Half of Image
2
× (
Number of scan lines in first half of image
Pixels per byte
×
240 = 38400 bytes = 9600h bytes
640
--------- -
4
= 00A0h bytes per scan line
480
= --------- - = 240 scan lines
2
S18A-G-002-02
)