Svenska ElektronikForumet

Kod: Markera allt

timer1:                   ; Interupt som utförs en gång per sekund med hjälp av timer1 match A
ld      temp,   X    ; Hämtar gammalt värde som finns i adress X
sub      sum,   temp      ; Drar ifrån gammalt värde från summan
st      X+,      cps          ; Stoppar in aktuellt (nytt) värde på det gamla värdets plats och flyttar fram pekaren
add      sum,   cps        ; Lägger till aktuellt (nytt) värde till summan
cpi      XL,      buff_length  ; Jämför pekaren med buffertlängden
brne   _timer1                     ;Är bufferten inte slut? Hoppa till timer
ldi      XL,      avg_buff_L      ; Annars återställ pekaren
_timer1: 
mov      avg,   sum    ; Flytta summan till avg

ror      avg   ; Dividera med 8 genom att dividera med två tre gånger.
clc 
ror      avg 
clc 
ror      avg 
clc 
reti

Kod: Markera allt

.def 	data = 	r0
.def	temp =	r16
.def	temp2 =	r17
.def	cps =	r18
.def	avg =	r19
.def	hex =	r20
.def	dig1 =	r21
.def	dig2 =	r22
.def	dig3 =	r23
.def	sum =	r24

.equ	avg_buff_H =	0x01
.equ	avg_buff_L =	0x00
.equ	buff_length = 8

ldi		XH,		avg_buff_H
ldi		XL,		avg_buff_L 

Kod: Markera allt

.include "m88def.inc" 

; 8 MHz external chrystal

.org	0x000
rjmp	Reset

.org	INT0addr	; Interuptvector external INT0
rjmp	count

.org	OC1Aaddr	; Interuptvektor timer 1 match A
rjmp	timer1


;--------------------------
; initialise Stack Pointer
;--------------------------
reset:
ldi 	r16, 	low(RAMEND)
out 	SPL, 	r16

;--------------------------
; Set definitions
;--------------------------
.def 	data = 	r0
.def	temp =	r16
.def	temp2 =	r17
.def	cps =	r18
.def	avg =	r19
.def	hex =	r20
.def	dig1 =	r21
.def	dig2 =	r22
.def	dig3 =	r23
.def	sum =	r24

.equ	avg_buff_H =	0x01
.equ	avg_buff_L =	0x00
.equ	buff_length = 8



ldi		XH,		avg_buff_H
ldi		XL,		avg_buff_L 
ldi		temp,	0
zero_buffer:
st		X+,		temp
cpi		XL,		buff_length
brne	zero_buffer
ldi		XH,		avg_buff_H
ldi		XL,		avg_buff_L

ldi		sum,	0

;--------------------------
; USART init
;--------------------------
;set baudrate
ldi		temp,	(0<<U2X0)
sts		UCSR0A,	temp
ldi		temp,	51 ; 51 - 9600 Baud @ 8 MHz
sts		UBRR0L, temp
;enable transmitter
ldi		temp,	(1<<TXEN0)
sts		UCSR0B,	temp
;set frame format 8n1
ldi		temp,	(1<<UCSZ00)|(1<<UCSZ01)
sts		UCSR0C,	temp

;--------------------------
; Set interupts
;--------------------------

ldi		temp,	(1<<INT0) ; Extern interupt INT0
out		EIMSK,	temp
ldi		temp,	(1<<ISC01)|(1<<ISC00) ; Rising edge
sts		EICRA,	temp

ldi		temp,	75	; Sätter timer compare
ldi		temp2,	255	; 75 ger ungefär 2,5 sek
sts		OCR1AH,	temp
sts		OCR1AL,	temp2

ldi		temp,	(1<<OCIE1A) ; Timer match A interupt
sts		TIMSK1,	temp
ldi		temp,	(1<<CS12)|(1<<CS10)|(1<<WGM12) ; Timer1 prescaler 1024 & CTC
sts		TCCR1B,	temp
sei							; Global interupt on


;--------------------------
; Main program
;--------------------------
main:


rjmp main




;--------------------------
; Timer interupt 1
;--------------------------
timer1:

;Provar medelvärdesbildning....



ld		temp,	X
sub		sum,	temp
st		X+,		cps
add		sum,	cps	
cpi		XL,		buff_length
brne	_timer1
ldi		XH,		avg_buff_H
ldi		XL,		avg_buff_L
_timer1:



mov		avg,	sum
ror		avg
clc
ror		avg
clc
ror		avg
clc



;Slut prov medelvärdesbildning


;Presentera på RS232

ldi 	ZL, 	LOW(text_cps*2) ;set Low memory pointer
ldi 	ZH, 	HIGH(text_cps*2) ;set High memory pointer
rcall	transmitt

mov		hex,	cps
rcall	bcd


ldi 	ZL, 	LOW(text_cpsavg*2) ;set Low memory pointer
ldi 	ZH, 	HIGH(text_cpsavg*2) ;set High memory pointer
rcall	transmitt


mov		hex,	avg
rcall	bcd


ldi 	ZL, 	LOW(text_crlf*2) ;set Low memory pointer
ldi 	ZH, 	HIGH(text_crlf*2) ;set High memory pointer
rcall	transmitt


ldi		cps,	0
reti



;--------------------------
; Transmitt via RS232
;--------------------------
transmitt:
rcall	ready_tx
lpm
mov		temp,	data
cpi		temp,	'#'
breq	transmitt1
sts 	UDR0,	data
adiw 	ZL,1
rjmp	transmitt
transmitt1:
ret


;--------------------------
; Count pulse
;--------------------------
count:
inc		cps
reti

 
;--------------------------
; Hex to ascii and out rs232
;--------------------------
;input: hex = 8 bit value 0 ... 255 
;output: dig1, dig2, dig3 = digits 
bcd: 
ldi		dig1,	-1 + '0' 
_bcd1: 
inc 	dig1 
subi 	hex,	100 
brcc	_bcd1 
ldi 	dig2,	10 + '0' 
_bcd2: 
dec		dig2
subi 	hex,	-10 
brcs 	_bcd2 
sbci 	hex, 	-'0' 
mov		dig3,	hex

rcall	ready_tx
cpi		dig1,	'0'
brne	_bcd3
ldi		dig1,	' '
_bcd3:
sts		UDR0,	dig1

rcall	ready_tx
cpi		dig2,	'0'
brne	_bcd4
cpi		dig1,	' '
brne	_bcd4
ldi		dig2,	' '
_bcd4:
sts		UDR0,	dig2

rcall	ready_tx
sts		UDR0,	dig3

ret 

;--------------------------
; waits for tx ready
;--------------------------
ready_tx:
lds		temp,	UCSR0A
sbrs 	temp,	UDRE0
rjmp	ready_tx
ret



;--------------------------
; Dialog text
;--------------------------
.CSEG
text_cps:
.db "cps: #"
text_cpsavg:
.db "     cps avg: #"
text_crlf:
.db 10,13,"#"

Kod: Markera allt

ld		temp,	X
sub		sum,	temp
st		X+,		cps
add		sum,	cps	
andi	XL,		buff_length - 1

mov		avg,	sum
clc
ror		avg
clc
ror		avg
clc
ror		avg