Arizona Picdem 17 ユーザーズマニュアル

DS39024B-page 44

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 2001 Microchip Technology Inc.

{

// The data bits must be either a 8-bit port or the upper or

// lower 4-bits of a port. These pins are made into inputs

#ifdef BIT8

// 8-bit mode, use 

whole port

DATA_PORT = 0;

TRIS_DATA_PORT = 0xff;

#else

// 4-bit mode

#ifdef UPPER

// Upper 4-bits of 

the port

DATA_PORT &= 0x0f;

TRIS_DATA_PORT |= 0xf0;

#else

// Lower 4-bits of 

the port

DATA_PORT &= 0xf0;

TRIS_DATA_PORT |= 0x0f;

#endif

#endif

TRIS_RW = 0;

// All control sig-

nals made outputs

TRIS_RS = 0;

TRIS_E = 0;

RW_PIN = 0;

// R/W pin made low

RS_PIN = 0; 

// Register select 

pin made low

E_PIN = 0;

// Clock pin made low

// Delay for 15ms to allow for LCD Power on reset

DelayPORXLCD();

// Setup interface to LCD

#ifdef BIT8

// 8-bit mode inter-

face

TRIS_DATA_PORT = 0;

// Data port output

DATA_PORT = 0b00110000;

// Function set 

cmd(8-bit interface)

#else

// 4-bit mode inter-

face

#ifdef UPPER

// Upper nibble 

interface

TRIS_DATA_PORT &= 0x0f;

DATA_PORT &= 0x0f;

DATA_PORT |= 0b00110000;

// Function set 

cmd(4-bit interface)

#else

// Lower nibble 

interface

TRIS_DATA_PORT &= 0xf0;

DATA_PORT &= 0xf0;

DATA_PORT |= 0b00000011;

// Function set 

cmd(4-bit interface)

#endif

#endif

E_PIN = 1;

// Clock the cmd in

DelayFor18TCY();

E_PIN = 0;

// Delay for at least 4.1ms

DelayXLCD();