Epson Research and Development
Page 37
Vancouver Design Center
Programming Notes and Examples
S1D13503
Issue Date: 01/01/30
X18A-G-002-06
4.2.2 Display Start Address Registers
This section illustrates how to properly calculate the values for the Screen Start Address Registers for a given LCD panel
resolution. However, this section is limited to single panel displays; refer to Section 5.4.3, “Dual Panel LCD” on page 48
to program the Screen Start Address Registers for a dual panel display.
In the following example, the Display Start Address Registers are programmed for a 16 color 320 x 240 single panel LCD
display. The technique shown, however, can also be used to calculate the memory map of other resolutions. In addition,
reference is made to the S5U13503B00C evaluation board; other hardware implementations of the S1D13503 may assign
different display and port addresses from those of the S5U13503B00C. Refer to the S5U13503B00C Evaluation Board
User’s Manual for more information on these hardware issues.
Example 9:
Program the Display Start Address Registers for a single LCD panel; the display is at-
tached to the S5U13503B00C evaluation board.
Normally images are loaded at the start of display memory (D000:0000h, bank 0), so the display start address registers must
be set to 0000h words.
AUX[06h] = 00h
AUX[07h] = 00h
Example 10: Program the Display Start Address Registers for a dual panel LCD.
Refer to Section 5.4.3.1, “Displaying a Single Image on a Dual Panel” on page 50.
Example 11: Determine if the S1D13503 implementation can support a 640 x 480 LCD with 4 colors.
1.
Calculate the number of bytes per scan line:
2.
Calculate the total number of bytes required for display memory:
3.
Compare the required number of bytes with the amount of memory available to the S1D13503.
•
The S1D13503 has 128k available, so there is 131,072 bytes available. Since this number is greater than the
76,800 bytes required for 640 x 480 with 4 colors, the S1D13503 implementation can support a 640 x 480 LCD
with 4 colors.
Note
The memory required for 4 colors at 640 x 480 is the same as the memory required for 4 gray shades at
640 x 480. Consequently the S1D13503 implementation can also support a 640 x 480 LCD with 4 gray
shades.
pixels per scan line
pixels per byte
----------------------------------------------
640
4
---------
160 bytes per scan line
=
=
160 bytes per scan line
(
)
480 scan lines
(
)
76800 bytes
=
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