HD66781 Datasheet, PDF (32/196 Pages) Renesas Technology Corp – 720-channel Source Driver for a-Si TFT/Low Temperature Poly-Si TFT Panels with 262,144-color display RAM

HD66781
Preliminary
Instruction
Outline
The HD66781 adapts an 18-bit bus architecture that enables high-speed interfacing with high-performance
microcomputers. The HD66781 starts internal processing of 18/16/9/8/-bit data sent from external after
storing control information in the instruction register (IR) and data register (DR). Since the internal
operation of HD66781 is determined by signals sent from the microcomputer, register selection signal (RS),
read/write signal (R/W), and internal 16-bit data bus signals (DB15 to DB0) are called instructions. GRAM
is accessed through internal 18-bit data bus. The HD66781 has ten categories of instruction.
1. Specify index
2. Read status
3. Control display
4. Power management control
5. Graphics data processing
6. Set internal GRAM address
7. Transfer data to and from internal GRAM
8. Make an internal γ-adjustment
9. Control a panel
10. Control OSD display
Normally, the instruction to write data on GRAM is used the most often. The address of internal GRAM is
updated automatically after data are written to the internal GRAM. With window address function, this
reduces the amount of data transmission to minimum and thereby lightens the load on the program
processed by the microcomputer. Since instructions are executed in 0 cycle, it is possible to write
instructions consecutively.
Rev.0.5, July.31.2003, page 32 of 196