Move Bitblt In A Positive Direction With Rop - Epson S1D13506 Technical Manual

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Note

10.2.5 Move BitBLT in a Positive Direction with ROP

Note
Programming Notes and Examples
Issue Date: 02/03/21
6. Program the BitBLT Color Format Register for 16 bpp operations. REG[101h] is set
to 01h.
7. Program the BitBLT Memory Offset Registers to the ScreenStride in WORDS.
BltMemoryOffset = ScreenStride ÷ 2
REG[10Dh] is set to 02h and REG[10Ch] is set to 80h.
8. Program the BitBLT Destination/Source Linear Select bits for a rectangular blit (Bit-
BLT Destination Linear Select = 0, BitBLT Source Linear Select = 0).
Start the blit operation. REG[100h] is set to 80h.
The order of register initialization is irrelevant as long as all relevant registers are pro-
grammed before the BitBLT is initiated.
The Move BitBLT moves an area of the display buffer to a different area of the display
buffer. This operation has two intended purposes:
• Copying unattended display buffer to display buffer.
• Saving a visible bitmap to off-screen display buffer.
The Move BitBLT may move data from one rectangular area to another, or it may be
specified as linear. This allows the temporary saving of a portion of the visible display
buffer to an area off-screen. The linear configuration may be applied to the source or desti-
nation. Defining the Move BitBLT as linear allows each line of the Move BitBLT area to
be placed directly after the previous line, rather than requiring a complete row of address
space for each line.
When the destination area overlaps the original source area and the destination address
is greater then the source address, use the Move BitBLT in Negative Direction with
ROP.
= 640
= 280h
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