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Epson Research and Development
Vancouver Design Center
S1D13503
Programming Notes and Examples
X18A-G-002-06
Issue Date: 01/01/30
•
If the line count is set to 99, then the first 100 scan lines of image 1 are shown, following by the first part of im-
age 2 (see Figure 17).
AUX[0Ah] = 63h (99 decimal)
AUX[0Bh] = 00h
Figure 17: 320 x 240 Single Panel For Split Screen
9.
Write both image 1 and image 2 to their respective locations in display memory.
5.4.3 Dual Panel LCD
The following is the procedure to show a split screen image on a 4 gray shade 640 x 480 dual panel LCD. For this example
the S5U13503B00C is used with the Memory Interface set to 16 bits (required for 128k of display memory). In addition,
the two images shown on the split screen are each 640 x 240.
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 ad-
dresses 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.
3.
Determine the display memory location for image 1.
For simplicity, assign the beginning of display memory as the starting address of image 1 (see Figure 16). For the
S5U13503B00C, this address is D000:0000h, bank 0.
4.
Program the Screen 1 Display Start Address Register to point to the beginning of image 1.
Since image 1 is at the beginning of display memory, program the Screen 1 Display Start Address Register to 0000h.
AUX[06h] = 00h
AUX[07h] = 00h
5.
Calculate the total number of bytes required for image 1.
Scan Line 0
Image 1
...
Scan Line 99
Scan Line 100
Image 2
...
Scan Line 239
Screen 1 Display Line Count Register = 99 lines
4 gray shades => 2 bits per pixel
2 bits per pixel => 4 pixels per byte
number of bytes per scan line
pixels per scan line
pixels per byte
----------------------------------------------
640
4
---------
160 bytes per scan line
00A0h bytes per scan line
=
=
=
=
bytes per scan line
(
)
number of scan lines for image 1
(
)
×
160
240
×
38400 bytes
9600h bytes
=
=
=
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