;LCD support module

;----------------------------------------------------------------------------

;Constantes:

.equ	CONTRAST	= 255	

;----------------------------------------------------------------------------

.DSEG	;Data segment

;----------------------------------------------------------------------------

.CSEG	;Code segment

;----------------------------------------------------------------------------

;LCD init:

iLCD:	ldi	temp,(1<<COM1A1) | (1<<COM1A0) | (1<<WGM10)
	out	TCCR1A,temp
	ldi	temp,(1<<CS10)	;CLK/1
	out	TCCR1B,temp
	ldy	CONTRAST
	out	OCR1AL,YL	;contrast PWM
	out	OCR1AH,YH

	ldi	Cnt,15
	rcall	mDel		;initial delay

	ldi	temp,0x30
	rcall	LCD_WC		;write command to LCD
	ldi	Cnt,5
	rcall	mDel		;delay >4.1mS

	ldi	temp,0x30
	rcall	LCD_WC		;write command to LCD
	ldi	Cnt,100
	rcall	uDel		;delay >100uS

	ldi	temp,0x30
	rcall	LCD_WC		;write command to LCD
	ldi	Cnt,5
	rcall	mDel		;delay >4.1mS

	ldi	temp,0x38	;FUNCTION SET
	rcall	LCD_WC		;write command to LCD
	ldi	Cnt,15
	rcall	mDel

	ldi	temp,0x0C	;DISPLAY ON
	rcall	LCD_WC		;write command to LCD
	ldi	Cnt,15
	rcall	mDel

	ldi	temp,0x06	;ENTRY MODE SET
	rcall	LCD_WC		;write command to LCD
	ldi	Cnt,15
	rcall	mDel

	rcall	LCD_CL		;clear LCD
	ldi	Cnt,15
	rcall	mDel
	rcall	LCD_HI		;print splash screen
	ret

;----------------------------------------------------------------------------

;Type char:
;Input:	temp - char code:
;	0x10 - LCD clear

LCD_CH:	push	Cnt
	cpi	temp,0x10
	brne	ch1
	rcall	LCD_CL		;clear LCD
	rjmp	chr
ch1:	rcall	LCD_WD		;type char
chr:	pop	Cnt
	ret

;----------------------------------------------------------------------------

;Set position:
;Input:	YL - Line (1..2)
;	YH - Pos (1..16)

LCD_XY:	push	temp
	push	Cnt
	dec	YL
	dec	YH
	ldi	temp,0x80
	bbrc	YL,0,xy1
	ori	temp,0x40
xy1:	add	temp,YH
	rcall	LCD_WC
	pop	Cnt
	pop	temp
	ret

;----------------------------------------------------------------------------

;Clear LCD:

LCD_CL:	ldi	temp,0x01	;DISPLAY CLEAR
	rcall	LCD_WC		;write command to LCD
	ldi	Cnt,5
	rcall	mDel		;delay >1.64mS
	ret

;----------------------------------------------------------------------------

;Write command to LCD:
;Input:	temp - data byte

LCD_WC:	Port_LCD_RS_0		;RS <- 0
	rcall	LCD_WR		;write byte to LCD
	ret

;----------------------------------------------------------------------------

;Write data to LCD:
;Input:	temp - data byte

LCD_WD:	Port_LCD_RS_1		;RS <- 1
	rcall	LCD_WR		;write byte to LCD
	ret

;----------------------------------------------------------------------------

;Write byte to LCD:
;Input:	temp - data byte

LCD_WR:	Out_Data_temp		;out data
	Port_LCD_W_0
	Port_LCD_E_1		;E <- 1
	ldi	Cnt,2
	rcall	uDel		;delay 2 uS
	Port_LCD_E_0		;E <- 0
	ldi	Cnt,50
	rcall	uDel		;delay 50 uS
	ret

;----------------------------------------------------------------------------

;Delay:
;Cnt - delay value, uS (2uS min)
;CAUTION! TIMED CODE!

uDel:	dec	Cnt
	nop
	nop
	nop
	nop
	nop
De:	dec	Cnt
	nop
	nop
	nop
	nop
	nop
	nop
	nop
	nop
	nop
	brne	De
	ret			

;----------------------------------------------------------------------------

;Delay:
;Cnt - delay value, mS

mDel:	push	YL
	push	YH
	mov	YH,Cnt
md2:	ldi	YL,5		;outer loop, 1mS
md1:	ldi	Cnt,200		;inner loop, 200uS
	rcall	uDel
	dec	YL
	brne	md1
	rcall	mWdog		;restart watchdogs
	dec	YH
	brne	md2
	pop	YH
	pop	YL
	ret

;----------------------------------------------------------------------------

;Print null-terminated string:
;Input:	ZH:ZL - pointer to string in FLASH

LCD_ST:	lpm	temp,Z+
	tst	temp
	breq	lstr
	rcall	LCD_CH		;type char
	rjmp	LCD_ST
lstr:	ret

;----------------------------------------------------------------------------

;Print splash screen:

LCD_HI:	ldi	YL,1
	ldi	YH,1
	rcall	LCD_XY
	table	Sp1
	rcall	LCD_ST

	ldi	YL,2
	ldi	YH,1
	rcall	LCD_XY
	table	Sp2
	rcall	LCD_ST
	ret

;----------------------------------------------------------------------------

;	     1234567890123456            
Sp1:	.db "BC1602E 1-Y-PLCW",0,0
Sp2:	.db "Bolymin QC OK 04",0,0

;----------------------------------------------------------------------------