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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
Each image can be scrolled or panned by appropriate programming of the respective Display Start Address Registers. The
following are some examples:
•
To scroll image 1 up, the Screen 1 Start Address Register must point to the following scan line.
AUX[06h] = LSB of Screen 1 Display Start Address
AUX[07h] = MSB of Screen 1 Display Start Address
•
To scroll image 2 down, the Screen 2 Start Address Register must point to the previous scan line.
AUX[08h] = LSB of Screen 2 Display Start Address
AUX[09h] = MSB of Screen 2 Display Start Address
•
To pan image 1 to the right by a group of pixels, the Screen 1 Start Address Register must be increased by 1.
AUX[06h] = LSB of Screen 1 Display Start Address
AUX[07h] = MSB of Screen 1 Display Start Address
See Section 5.5.2, “Panning Right and Left” on page 52 for more information.
•
To pan image 2 to the left by a group of pixels, the Screen 2 Start Address Register must be decreased by 1.
AUX[08h] = LSB of Screen 2 Display Start Address
AUX[09h] = MSB of Screen 2 Display Start Address
See Section 5.5.2, “Panning Right and Left” on page 52 for more information.
5.4.3.1 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 S5U13503B00C is used with a 4 gray shade 640 x 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 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.
Screen 1 Display Start Address
Screen 1 Display Start Address
number of bytes per scan line
2 bytes per word
----------------------------------------------------------------------
+
=
Screen 2 Display Start Address
Screen 2 Display Start Address
number of bytes per scan line
2 bytes per word
----------------------------------------------------------------------
–
=
Screen 1 Display Start Address
Screen 1 Display Start Address
1
+
=
Screen 2 Display Start Address
Screen 2 Display Start Address
1
–
=
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
=
=
=
=
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