
Page 70
Epson Research and Development
Vancouver Design Center
S1D13A05
Programming Notes and Examples
X40A-G-003-04
Issue Date: 2002/08/21
BitBLT Operation
The BitBLT Operation selects which BitBLT operation performed. The following table
lists the available BitBLT operations.
Table 9-3 : BitBLT Operation Selection
BitBLT Operation
Bits [3:0]
BitBLT Operation
0000
Write BitBLT with ROP
This operation refers to BitBLTs where data is to be transferred from system memory to display memory
0001
Read BitBLT
This operation refers to BitBLTs where data is to be transferred from display memory to system memory
0010
Move BitBLT in positive direction with ROP
This operation is used to transfer data from display memory to display memory
0011
Move BitBLT in negative direction with ROP
This operation is used to transfer data from display memory to display memory
0100
Transparent Write BitBLT
Like the Write BitBLT this operation is used when transferring data from system memory to display
memory, the difference is that destination pixels will be left “as is” when source pixels of a specified color
are encountered.
0101
Transparent Move BitBLT in positive direction
As with the Move BitBLTs this operation is used to transfer data from display memory to display memory.
The difference is that destination pixels will be left “as is” when source pixels of a specified color are
encountered.
0110
Pattern Fill with ROP
Fills the specified area of display memory with a repeating pattern stored in display memory.
0111
Pattern Fill with transparency
As with the Pattern Fill, this BitBLT fills a specified area of display memory with a repeating pattern,
destination pixels will be left “as is” when source pixels of a specified color are encountered.
1000
Color Expansion
This BitBLT expands the bits of the source data into full pixels at the destination. If a source bit is 0 the
destination pixel will be background color and if the source bit is 1 the destination pixel will be of foreground
color. The source data for Color Expansion BitBLTs is always system memory.
1001
Color Expansion with transparency
Like the Color Expansion BitBLT, this operations expands each bit of the source data to occupy a full
destination pixel. The difference, is that destination pixels corresponding to source bits of 0 will be left “as
is”. The data source is system memory
1010
Move BitBLT with Color Expansion
This BitBLT works the same as the Color Expansion BitBLT however the source of the BitBLT is display
memory.
1011
Move BitBLT with Color Expansion and transparency
This BitBLT works the same as the Color Expansion with Transparency BitBLT however the source of the
BitBLT is display memory.
1100
Solid Fill BitBLT
Use this BitBLT to fill a given area with one solid color.
Other
combinations
Reserved