HD66740 Datasheet, PDF (16/95 Pages) Hitachi Semiconductor – 112 x 80-dot Graphics LCD Controller/Driver

HD66740
Instructions
Outline
Only the instruction register (IR) and the data register (DR) of the HD66740 can be controlled by the
MPU. Before starting internal operation of the HD66740, control information is temporarily stored in
these registers to allow interfacing with various peripheral control devices or MPUs which operate at
different speeds. The internal operation of the HD66740 is determined by signals sent from the MPU.
These signals, which include the register selection signal (RS), the read/write signal (R/W), and the data
bus signal (DB0 to DB7), make up the HD66740 instructions. There are four categories of instructions
that:
• Control the display
• Control power management
• Set internal RAM addresses
• Transfer data with the internal RAM
Normally, instructions that perform data transfer with the internal RAM are used the most. However,
auto-incrementation by 1 (or auto-decrementation by 1) of internal HD66740 RAM addresses after each
data write can lighten the MPU program load.
Because instructions are executed in 0 cycle, instructions can be written in succession.
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