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Epson Research and Development
Vancouver Design Center
Note
The order of register initialization is irrelevant as long as all relevant registers are pro-
grammed before the BitBLT is initiated.
10.2.3 Color Expand BitBLT With Transparency
This BitBLT operation is virtually identical to the Color Expand BitBLT, except the
background color is completely ignored. All bits set to 1 in the source monochrome bitmap
are color expanded to the foreground color. All bits set to 0 that would be expanded to the
background color in the Color Expand BitBLT are not expanded at all.
Program REG[103h] to 09h instead of 08h. Programming the background color is not
required.
10.2.4 Solid Fill BitBLT
The Solid Fill BitBLT fills a rectangular area of the display buffer with a solid color. This
operation is used to paint large screen areas or to set areas of the display buffer to a given
value.
Example 11: Fill a red 9 x 321 rectangle at the screen coordinates x = 100, y = 10 us-
ing a 640x480 display at a color depth of 16 bpp.
1. Calculate the destination address (upper left corner of the destination rectangle) using
the following formula.
DestinationAddress = (y × ScreenStride) + (x × BytesPerPixel)
= (10 × (640 × 2)) + (100 × 2)
= 13000
= 32C8h
where:
BytesPerPixel = 1 for 8 bpp
BytesPerPixel = 2 for 15/16 bpp
ScreenStride = DisplayWidthInPixels × BytesPerPixel = 1280 for 16 bpp.
Program the BitBLT Destination Start Address Registers. REG[10Ah] is set to 00h,
REG[109h] is set to 32h, and REG[108h] is set to C8h.
2. Program the BitBLT Width Registers to 9 - 1. REG[111h] is set to 00h and
REG[110h] is set to 08h.
3. Program the BitBLT Height Registers to 321 - 1. REG[113h] is set to 01h and
REG[112h] is set to 40h (320 decimal).
4. Program the BitBLT Foreground Color Registers. REG[119h] is set to F8h and
REG[118h] is set to 00h (Full intensity red in 16 bpp is F800h).
5. Program the BitBLT Operation Register to select Solid Fill. REG[103h] is set to 0Ch.
S1D13506
X25B-G-003-03
Programming Notes and Examples
Issue Date: 01/02/06
EPSON [ EPSON COMPANY ]
