LCDasm.asm

// * Author: Victor Dueñas Guardia
// * Info: www.netzek.com

.INCLUDE "M16DEF.INC"
.equ LCD_RS	= 0
.equ LCD_RW	= 1
.equ LCD_E	= 2
	LDI R16,HIGH(RAMEND)
	OUT SPH,R16
	LDI R16,LOW(RAMEND)
	OUT SPL,R16
	CALL INICIAR_LCD
	LDI R29,HIGH(MENSAJE)
	LDI R28,LOW(MENSAJE)
	CALL RETARDO
	CALL SEND_STRING
BUCLE:
	RJMP BUCLE
	
INICIAR_LCD:
	LDI R16,$FF;
	OUT DDRA,R16
	OUT DDRB,R16
	
	CBI PORTB,LCD_E
	CBI PORTB,LCD_RS
	CBI PORTB,LCD_RW
	LDI R16,$38;
	OUT PORTA,R16
	SBI PORTB,LCD_E
	CBI PORTB,LCD_E
	
	CBI PORTB,LCD_E
	CBI PORTB,LCD_RS
	CBI PORTB,LCD_RW
	LDI R16,$0F;
	OUT PORTA,R16
	SBI PORTB,LCD_E
	CBI PORTB,LCD_E
	
	CBI PORTB,LCD_E
	CBI PORTB,LCD_RS
	CBI PORTB,LCD_RW
	LDI R16,$06;
	OUT PORTA,R16
	SBI PORTB,LCD_E
	CBI PORTB,LCD_E
	
	RET

SEND_CHAR:
	//Caracter en R18
	SBI PORTB,LCD_RS
	CBI PORTB,LCD_RW
	CBI PORTB,LCD_E
	OUT PORTA,R18
	SBI PORTB,LCD_E
	CBI PORTB,LCD_E
	CALL RETARDO
	RET

SEND_STRING:
	//Envia mensaje direccionado por Y
	LDI R23,0

SEGUIR:
	MOVW R31:R30,R29:R28
	MOV R22,R23
	ADD R30,R22
	EOR R22,R22
	ADC R31,R22
	CLC
	ROL R30
	ROL R31
	LPM R18,Z
	CPI R18,$FF
	BREQ SALIR
	CALL SEND_CHAR
	
	ORI R30,$01
	LPM R18,Z
	CPI R18,$FF
	BREQ SALIR
	CALL SEND_CHAR
	
	INC R23
	JMP SEGUIR
SALIR:
	RET
	
RETARDO:
	LDI R21,31
BUCLE_EXTERNO:
	LDI R20,255
BUCLE_INTERNO:
	NOP
	NOP
	NOP
	NOP
	NOP
	NOP
	NOP
	DEC R20
	BRNE BUCLE_INTERNO
	DEC R21
	BRNE BUCLE_EXTERNO
	RET

.CSEG
.ORG 0X0100
MENSAJE:
.DB "ATmega16",$FF;