;; ＴＷＩ接続の16x2液晶表示パネルに文字を表示させる
;; 
;;
;***************************************************************
;*       　デバイスの定義ファイルのインクルード                *
;***************************************************************
;
.include    "m88def.inc"
;
;***************************************************************
;*      　シンボルをレジスターにシンボル名を定義               *
;***************************************************************
;
.def	temp	=r16	;テンポラリ
.def	cnt1	=r17	;ディレイルーチンで使用する変数
.def	cnt2	=r18
.def	cnt3	=r19
.def	CTRL_data =r20
.def	TWI_data  =r21
;
.equ	SLA	=0b01111100	;LCD I2C address $7C
.equ	SLA_W	=SLA
.equ	SLA_R	=0b01111101	;SLA | 0b00000001
.equ	Inst_ctrl = 0b00000000
.equ	Data_ctrl = 0b01000000
;
;
;***************************************************************
;*                      ベクトルエリア                         *
;***************************************************************
	.cseg
	rjmp	reset   ;  reset vector
	reti            ;  INT0  vector
	reti		;  INT1  vector
	reti		;  PCINT0
	reti		;  PCINT1
	reti		;  PCINT2
	reti		;  WDT
	reti		;  Timer2 COMPA
	reti		;  Timer2 COMPB
	reti		;  Timer2 overflow
	reti		;  Timer1 capture
	reti		;  Timer1 COMPA
	reti		;  Timer1 COMPB
	reti		;  Timer1 overflow
	reti		;  Timer0 COMPA
	reti		;  Timer0 COMPB
	reti		;  Timer0 overflow
	reti		;  SPI STC
	reti		;  USART/Rx complete
	reti		;  USART/ Data register empty
	reti		;  USART/Tx complete
	reti		;  ADC
	reti		;  EEPROM EE_RDY
	reti		;  Analog comparator
	reti		;  TWI
	reti		;  SPM_RDY
;
;
;***************************************************************
;*                    リセットルーチン　　　　　　　　　　　　 *
;***************************************************************
reset:
	ldi	temp,high(RAMEND)
	out	SPH,temp	; set stuck pointer
	ldi	temp,low(RAMEND)
	out	SPL,temp	; set stuck pointer
;
	ldi	temp, 0b11111111
	out	DDRB, temp
	out	PORTB, temp
;*****************************************
;TWI 初期化
; まず，40ms　待つ
;
	ldi	cnt1, 40	; 40ms delay
	rcall	delay
;
; SCL周波数　100kHz
;
	ldi	temp, 32	;8000000/(16+2*1*32)
	sts	TWBR, temp
	ldi	temp, 0
	sts	TWSR, temp

	ldi	temp, (1<<TWEN)
	sts	TWCR, temp
;
	ldi	CTRL_data, Inst_ctrl
;
; Function set $38: 8bit 2line 5x8dots
;
	ldi	TWI_data, $38
	rcall	TWI_send
	ldi	cnt1, 1		; 1ms delay
	rcall	delay
;
; Function set $39: 拡張機能選択
;
	ldi	TWI_data, $39
	rcall	TWI_send
	ldi	cnt1, 1		; 1ms delay
	rcall	delay
;
; Function set $14: bias 1/5, Frame Freq. 183Hz
;
	ldi	TWI_data, $14
	rcall	TWI_send
	ldi	cnt1, 1		; 1ms delay
	rcall	delay
;
; ctrlrast set $73: 0011 
;
	ldi	TWI_data, $73
	rcall	TWI_send
	ldi	cnt1, 1		; 1ms delay
	rcall	delay
;
; Power/ICON/ctrlrast CTRL_datarol $56:
;  ICON off, booster circuit ON,ctrlrast 10
;
	ldi	TWI_data, $56
	rcall	TWI_send
	ldi	cnt1, 1		; 1ms delay
	rcall	delay
;
; Follower ctrlrol $6C: 
;  Follower circuit ON, V0 generator amplified ratio 011
;
	ldi	TWI_data, $6C
	rcall	TWI_send
	ldi	cnt1, 200	; 200ms delay
	rcall	delay
;
; Function set $38: 標準機能に戻る
;
	ldi	TWI_data, $38
	rcall	TWI_send
	ldi	cnt1, 1		; 1ms delay
	rcall	delay
;
; Clear Display $01
;
	ldi	TWI_data, $01
	rcall	TWI_send
	ldi	cnt1, 2		; 2ms delay
	rcall	delay
;
; Display ON/OFF ctrlrol $0C:
; Display ON, cursor OFF, Cursor blink OFF, 
;
	ldi	TWI_data, $0C
	rcall	TWI_send
	ldi	cnt1, 1		; 1ms delay
	rcall	delay
;
; LCD initialization end
;****************************************** 
	
;
;***************************************************************
;*                   メインプログラム                          *
;***************************************************************
;
main:
	ldi	CTRL_data, Inst_ctrl
	ldi	TWI_data, 0b10000000	;DDRAM address set
	rcall	TWI_send
	ldi	cnt1, 1
	rcall	delay
;
	ldi	TWI_data, 0b00000110	;Entry Mode 
	rcall	TWI_send
	ldi	cnt1, 1
	rcall	delay
;
	ldi	CTRL_data, Data_ctrl		;表示データ　RS=1

	ldi	TWI_data, 'W'
	rcall	TWI_send
	ldi	cnt1, 1
	rcall	delay
;
	ldi	TWI_data, 'e'
	rcall	TWI_send
	ldi	cnt1, 1
	rcall	delay
;
	ldi	TWI_data, 'l'
	rcall	TWI_send
	ldi	cnt1, 1
	rcall	delay
;
	ldi	TWI_data, 'c'
	rcall	TWI_send
	ldi	cnt1, 1
	rcall	delay
;
	ldi	TWI_data, 'o'
	rcall	TWI_send
	ldi	cnt1, 1
	rcall	delay
;
	ldi	TWI_data, 'm'
	rcall	TWI_send
	ldi	cnt1, 1
	rcall	delay
;
	ldi	TWI_data, 'e'
	rcall	TWI_send
	ldi	cnt1, 1
	rcall	delay
;
	ldi	TWI_data, ' '
	rcall	TWI_send
	ldi	cnt1, 1
	rcall	delay
;
	ldi	TWI_data, 'L'
	rcall	TWI_send
	ldi	cnt1, 1
	rcall	delay
;
	ldi	TWI_data, 'C'
	rcall	TWI_send
	ldi	cnt1, 1
	rcall	delay
;
	ldi	TWI_data, 'D'
	rcall	TWI_send
	ldi	cnt1, 1
	rcall	delay
;
	ldi	CTRL_data, Inst_ctrl
	ldi	TWI_data, 0b11000001	;2行目
	rcall	TWI_send
	ldi	cnt1, 1
	rcall	delay

	ldi	CTRL_data, Data_ctrl

	ldi	TWI_data, '&'
	rcall	TWI_send
	ldi	cnt1, 1
	rcall	delay
;
	ldi	TWI_data, ' '
	rcall	TWI_send
	ldi	cnt1, 1
	rcall	delay
;
	ldi	TWI_data, 'T'
	rcall	TWI_send
	ldi	cnt1, 1
	rcall	delay
;
	ldi	TWI_data, 'W'
	rcall	TWI_send
	ldi	cnt1, 1
	rcall	delay
;
	ldi	TWI_data, 'I'
	rcall	TWI_send
	ldi	cnt1, 1
	rcall	delay
;
	ldi	TWI_data, ' '
	rcall	TWI_send
	ldi	cnt1, 1
	rcall	delay
;
	ldi	TWI_data, 'S'
	rcall	TWI_send
	ldi	cnt1, 1
	rcall	delay
;
	ldi	TWI_data, 'a'
	rcall	TWI_send
	ldi	cnt1, 1
	rcall	delay
;
	ldi	TWI_data, 'm'
	rcall	TWI_send
	ldi	cnt1, 1
	rcall	delay
;
	ldi	TWI_data, 'p'
	rcall	TWI_send
	ldi	cnt1, 1
	rcall	delay
;
	ldi	TWI_data, 'l'
	rcall	TWI_send
	ldi	cnt1, 1
	rcall	delay
;
	ldi	TWI_data, 'e'
	rcall	TWI_send
	ldi	cnt1, 1
	rcall	delay
;
; 1 sec delay
	ldi	cnt1, 250
	rcall	delay
	ldi	cnt1, 250
	rcall	delay
	ldi	cnt1, 250
	rcall	delay
	ldi	cnt1, 250
	rcall	delay
;
; Clear Display $01
	ldi	CTRL_data, Inst_ctrl
	ldi	TWI_data, $01
	rcall	TWI_send
	ldi	cnt1, 2		; 2ms delay
	rcall	delay
;
;1 sec delay
	ldi	cnt1, 250
	rcall	delay
	ldi	cnt1, 250
	rcall	delay
	ldi	cnt1, 250
	rcall	delay
	ldi	cnt1, 250
	rcall	delay
;
	rjmp	main		; 次の入力待ち(to main)
;
;*******************************
;インストラクション送信
;
TWI_send:
;
; 1. 開始条件送出
;
	ldi	temp, (1<<TWINT)|(1<<TWSTA)|(1<<TWEN)
	sts	TWCR, temp
TW_wait1:
	lds	temp, TWCR
	sbrs	temp, TWINT
	rjmp	TW_wait1
	lds	temp, TWSR
	andi	temp, $F8
	cpi	temp, $08		;開始条件送信
	brne	ERROR
;
; 2. SLA+W送信
;
	ldi	temp, SLA_W
	sts	TWDR, temp
	ldi	temp, (1<<TWINT)|(1<<TWEN)
	sts	TWCR, temp
TW_wait2:
	lds	temp, TWCR
	sbrs	temp, TWINT
	rjmp	TW_wait2
	lds	temp, TWSR
	andi	temp, $F8
	cpi	temp, $18		;SLA+W送信ACK受信
	brne	ERROR
;
; 3. control byte 送信
;
	sts	TWDR, CTRL_data
	ldi	temp, (1<<TWINT)|(1<<TWEN)
	sts	TWCR, temp
TW_wait3:
	lds	temp, TWCR
	sbrs	temp, TWINT
	rjmp	TW_wait3
	lds	temp, TWSR
	andi	temp, $F8
	cpi	temp, $28		;control バイト送信ACK受信
	brne	ERROR
;
; 4. データ送信
;
	sts	TWDR, TWI_data
	ldi	temp, (1<<TWINT)|(1<<TWEN)
	sts	TWCR, temp
TW_wait4:
	lds	temp, TWCR
	sbrs	temp, TWINT
	rjmp	TW_wait4
	lds	temp, TWSR
	andi	temp, $F8
	cpi	temp, $28		;データバイト送信ACK受信
	brne	ERROR
;
; 5. 停止条件送出
;
	ldi	temp, (1<<TWINT)|(1<<TWSTO)|(1<<TWEN)
	sts	TWCR, temp
	ret
;
ERROR:
	cbi	PORTB, 0
;1 sec delay
	ldi	cnt1, 250
	rcall	delay
	ldi	cnt1, 250
	rcall	delay
	ldi	cnt1, 250
	rcall	delay
	ldi	cnt1, 250
	rcall	delay
	sbi	PORTB, 0
	ret
;
;
;*******************************************************************
;*               1 ms * cnt1 ディレイ ルーチン                     *
;*                                                                 *
;*   dl3: 5 clock * 228回 - 1                      = 1,139 clock   *
;*   dl2: (dl3 + 4 clock) * 7回 - 1                = 8,000 clock   *
;*   dl1: (dl2 + 4 clock) * cnt1回 -1 + 1 + 4 + 3  =      clock    *
;*                                                                 *
;*******************************************************************
;
delay:				;  dl1 + 1 + 4 + 3
dl1:				; (dl2 + 4 ) * 7 -1
	ldi	cnt2,7	; (1)
dl2:				; (dl3 + 4 ) * 228 -1
        ldi     cnt3,228	; (1)
dl3:				; 5 * 228 -1 = 1,139 clock
	nop			; (1)
	nop			; (1)
        dec     cnt3		; (1)
        brne    dl3      	;  if non-zero jump to dl3 (2/1)
	dec	cnt2		; (1)
	brne	dl2      	;  if non-zero jump to dl2 (2/1)
	dec	cnt1		; (1)
	brne	dl1      	;  if non-zero jump to dl1 (2/1)
	ret			; (4)