HD66760 Datasheet, PDF (49/105 Pages) Hitachi Semiconductor – 104 X 80-dot Graphics LCD Controller/Driver for 256 Colors

HD66760
Graphics Operation Function
The HD66760 can greatly reduce the load of the microcomputer graphics software processing through the 16-
bit bus architecture and internal graphics-bit operation function. This function supports the following:
1. A swap function that exchanges the upper and lower bytes in the 16-bit data sent from the
microcomputer.
2. A write data mask function that selectively rewrites some of the bits in the 16-bit write data.
3. A logical operation write function that writes the data sent from the microcomputer and the original
RAM data by a logical operation.
4. A conditional write function that compares the original RAM data or write data and the compare-bit
data and writes the data sent from the microcomputer only when the conditions match.
Even if the display size is large, the display data in the graphics RAM (GRAM) can be quickly rewritten.
The graphics bit operation can be controlled by combining the entry mode register, the bit set value of the
RAM-write-data mask register, and the read/write from the microcomputer.
Table 31 Graphics Operation
Operation Mode
Write mode 1
Bit Setting
I/D AM
0/1 0
LG2–0
000
Write mode 2
Write mode 3
0/1 1
0/1 0
000
110 111
Write mode 4
0/1 1 110 111
Read/write mode 1 0/1 0 001 010 011
Read/write mode 2 0/1 1 001 010 011
Read/write mode 3 0/1 0 100 101
Read/write mode 4 0/1 1 100 101
Operation and Usage
Horizontal data replacement, horizontal-border
drawing
Vertical data replacement, vertical-border drawing
Conditional horizontal data replacement, horizontal-
border drawing
Conditional vertical data replacement, vertical-
border drawing
Horizontal data write with logical operation,
horizontal-border drawing
Vertical data write with logical operation, vertical-
border drawing
Conditional horizontal data replacement, horizontal-
border drawing
Conditional vertical data replacement, vertical-
border drawing