Epson Research and Development Page 15
Vancouver Design Center
Hardware Functional Specification S1D13705
Issue Date: 02/02/01 X27A-A-001-10
4 Functional Block Diagram
Figure 4-1: System Block Diagram Showing Data Paths

4.1 Functional Block Descriptions

4.1.1 Host Interface

The Host Interface provides the means for the CPU/MPU to communicate with the dis play
buffer and internal registers.

4.1.2 Memory Controller

The Memory Controller arbitrates between CPU accesses and display refresh accesses. It
also generates the necessary signals to c ontrol the SRAM frame buffer.

4.1.3 Sequence Controller

The Sequence Controller controls data flow from the Memory Controller through t he Look-
Up Table and to the LCD Interface. It also generates memory addresses for display refr esh
accesses.
LCD
Memory
Controller
40k x 16-bit SRAM
LCD
Clocks
Power Save
Register
Sequence Controller
Look-Up
I/F
Generic MPU
MC68K
SH-3 Host
I/F
Bus Clock Memory Clock Pixel Clock
Table
SH-4