Файл: Microcontroller Programming. Thi Micro Chip PIC (Julio Sanchez, 2007).pdf

Сделать презентацию

Скачать файл (4,76Мб)

Заказать решение

ВУЗ: Не указан

Категория: Не указан

Дисциплина: Не указана

Добавлен: 14.06.2025

Просмотров: 8532

Скачиваний: 0

ВНИМАНИЕ! Если данный файл нарушает Ваши авторские права, то обязательно сообщите нам.

508		Chapter 15
movwf	TRISD	; and Port-D

;By default Port-A lines are analog. To configure them

;as digital code must set bits 1 and 2 of the ADCON1

;register (in bank 1)

movlw

0x06

; binary 0000 0110 is code to

; make all Port-A lines digital

movwf ADCON1

;Port-B, lines are wired to keypad switches, as follows:

;7 6 5 4 3 2 1 0

;| | | | |_|_|_|_____ switch rows (output)

;|_|_|_|_____________ switch columns (input)

;rows must be defined as output and columns as input

movlw	b’11110000’
movwf	TRISB
; TRIS Port-E for output
movlw	B’00000000’
movwf	TRISE	; TRIS Port-E

; Enable Port-B pullups for switches in OPTION register movlw b’00001000’

movwf OPTION_REG

;Back to bank 0 Bank0

;Initialize serial Port-for 2400 baud, 8 bits, no parity

;1 stop

call	InitSerial
; Test serial transmission by sending “RDY-”
movlw	‘R’
call	SerialSend
movlw	‘D’
call	SerialSend
movlw	‘Y’
call	SerialSend
movlw	‘-’
call	SerialSend
movlw	0x20
call	SerialSend
; Clear all output lines
movlw	b’00000000’
movwf	PORTD
movwf	PORTE
; Wait and initialize HD44780
call	delay_5	; Allow LCD time to initialize
itself
call	initLCD	; Then do forced
initialization
call	delay_5	; (Wait probably not
necessary)

; Clear character counter and line counter variables

Data EEPROM Programming		509
clrf	LCDcount
clrf	LCDline
; Set display address to start of first LCD line
call	line1
; Store address of display buffer
movlw	0x20
movwf	bufAdd
; Display “Receiving:” message prompt
call	blank20	; Clear buffer
movlw	0x00	; Offset in buffer
call	storeMS1	; Store message at offset
call	display20	; Display message
; Start address of EEPROM
clrf	EEMemAdd
; Setup for display in second line
call	line2
clrf	LCDline
incf	LCDline,f	; Set scroll control for
		; line 2

;============================================================

;receive serial data, store, and display ;============================================================ receive:

;Call serial receive procedure

call SerialRcv

;HOB of newData register is set if new data

;received

btfss	newData,7
goto	scanExit
; At this point new data was received.
movwf	EEByte	; Save received character
; Display character on LCD
movf	EEByte,w ; Recover character
call	send8	; Display in LCD
call	LCDscroll	; Scroll at end of line
; Store character in EEPROM at location in EEMemAdd
call	EEWrite	; Local procedure
incf	EEMemAdd,f	; Bump to next EEPROM

; Check for <Enter> key (0x0d) and execute display function

	movf	EEByte,w ; Recover last received
	sublw	0x0d
	btfsc	STATUS,Z ; Test if <Enter> key
	goto	isEnter	; Go if <Enter>
; Not <Enter> key, continue processing
scanExit:
	goto	receive	; Continue
;============================
;	display EEPROM data

510	Chapter 15

;============================

;This routine receives control when the <Enter> key is

;received.

;Action:

;1. Clear LCD

;2. Output is set to top LCD line

;3. Characters stored in EEPROM are displayed

;until 0x0d code is detected

isEnter:

call clearLCD

; Clear character counter and line counter variables clrf LCDcount

clrf LCDline

;Read data from EEPROM memory, starting at address 0

;and display on LCD until 0x0d terminator

call	line1
clrf	EEMemAdd ; Start at EEPROM 0
readOne:
call	EERead	; Get character
; Store character
movwf	EEByte	; Save character
; Test for terminator
sublw	0x0d
btfsc	STATUS,Z ; Test if 0x0d
goto	atEnd	; Go if 0x0d

;At this point character read is not 0x0d

;Display on LCD

movf	EEByte,w ; Recover character
; Display character on LCD
call	send8	; Display in LCD
call	LCDscroll	; Scroll at end of line
incf	EEMemAdd,f	; Next EEPROM byte
goto	readOne

; End of execution atEnd:

goto atEnd

;============================================================

;============================================================ ; L O C A L P R O C E D U R E S ;============================================================ ;============================================================ ;==========================

;init LCD for 4-bit mode ;========================== initLCD:

;Initialization for Densitron LCD module as follows:

Data EEPROM Programming

511

;4-bit interface

;2 display lines of 16 characters each

;cursor on

;left-to-right increment

;cursor shift right

;no display shift ;=======================|

;	set command mode		\|
;=======================\|
	bcf	PORTE,E_line		; E line low
	bcf	PORTE,RS_line		; RS line low
	bcf	PORTE,RW_line		; Write mode
	call	delay_125		; delay 125 microseconds
	movlw	0x28	; 0 0 1 0 1 0 0		0 (FUNCTION SET)
	call	send8	; 4-bit send routine
; Set 4-bit mode command must be repeated
	movlw	0x28
	call	send8
	movlw	0x0e	; 0 0 0 0 1 1 1		0 (DISPLAY ON/OFF)
	call	send8
	movlw	0x06	; 0 0 0 0 0 1 1		0 (ENTRY MODE SET)
	call	send8
	movlw	0x14	; 0 0 0 1 0 1 0		0 (CURSOR/DISPLAY
			;		SHIFT)
	call	send8
	movlw	0x01	; 0 0 0 0 0 0 0		1 (CLEAR DISPLAY)
			;		\|___ COMMAND BIT
	call	send8
	call	delay_5	; Test for busy
	return
.;===========================
;	procedure to clear LCD
;============================
clearLCD:
	bcf	PORTE,E_line		; E line low
	bcf	PORTE,RS_line		; RS line low
	bcf	PORTE,RW_line		; Write mode
	call	delay_125		; delay 125 microseconds
	movlw	0x01	; 0 0 0 0 0 0 0		1 (CLEAR DISPLAY)
			;		\|___ COMMAND BIT
	call	send8
	call	delay_5	; Test for busy
	return

;=======================

;Procedure to delay

;42 microseconds

512		Chapter 15
;=======================
delay_125:
movlw	.105	; Repeat 105 machine cycles
movwf	count1	; Store value in counter
repeat
decfsz	count1,f	; Decrement counter
goto	repeat	; Continue if not 0
return		; End of delay

;=======================

;Procedure to delay

;5 milliseconds ;======================= delay_5:

	movlw	.105	; Counter = 105 cycles
	movwf	count2	; Store in variable
delay:
	call	delay_125	; Delay
	decfsz	count2,f	; 40 times = 5 milliseconds
	goto	delay
	return		; End of delay
;========================
;	pulse E line
;========================
pulseE
	bsf	PORTE,E_line	; Pulse E line
	nop
	bcf	PORTE,E_line
	return
;=============================
;	long delay sub-routine
;=============================
long_delay:
	movlw	D’200’ ; w delay count
	movwf	J	; J = w
jloop:
	movwf	K	; K = w
kloop:
	decfsz	K,f	; K = K-1, skip next if zero
	goto	kloop
	decfsz	J,f	; J = J-1, skip next if zero
	goto	jloop
	return

;========================

;send 2 nibbles in

;4-bit mode ;========================

Смотрите также файлы

Microcontroller based applied digital control (D. Ibrahim, 2006).pdf

Kit 81 Simple PICMicro programmer (2002).pdf

Introduction to Verilog.pdf

Introduction to PIC Microcontrollers (Complete Guide to PIC).pdf

Introduction to Microcontrollers. Architecture, Programming, and Interfacing of the Motorola 68HC12 (G.J. Lipovski, 1999).pdf

Файл: Microcontroller Programming. Thi Micro Chip PIC (Julio Sanchez, 2007).pdf

Смотрите также файлы

Информация

Списки файлов

Дополнительно