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Epson Research and Development

Vancouver Design Center

4 VR4102 to S1D13504 Interface

4.1 Hardware Description

The NEC VR4102TM microprocessor is specifically designed to support an external LCD controller by providing the internal address decoding and control signals necessary. By using this interface only minimal external “glue” logic is necessary.

The diagram below shows a typical implementation of the VR4102 to S1D13504 interface.

NEC VR4102

Read/Write

S1D13504

Decode Logic

 

A0

WE0#

WR#

 

 

 

SHB#

 

WE1#

 

 

 

A0

RD0#

 

 

RD#

 

 

 

 

RD1#

LCDCS#

Pull-up

CS#

 

 

LCDRDY

 

WAIT#

 

A21

M/R#

 

 

 

System RESET

RESET#

ADD[25:0]

 

AB[20:0]

DAT[15:0]

 

DB[15:0]

BUSCLK

 

BUSCLK

Notes: The propagation delay of the Read/write Decode Logic shown above must be less than 10 nsec.

When connecting the S1D13504 RESET# pin, the system designer should be aware of all conditions that may reset the S1D13504 (e.g. CPU reset can be asserted during wake-up from power-down modes, or during debug states).

Figure 4-1: Typical Implementation of VR4102 to S1D13504 Interface

Note

For pin mapping see Table 3-1:, “Generic MPU Host Bus Interface Pin Mapping”.

S1D13504

Interfacing to the NEC VR4102™ Microprocessor

X19A-G-007-07

Issue Date: 01/02/02

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Image 396
Epson manual VR4102 to S1D13504 Interface, Read/Write, Decode Logic