LM35+AVR+7-segment display(.asm)
This tutorial is taken from the book MY EXPERIENCE IN PROGRAMMING AVR MICROCONTROLLER IN C USING WINAVR/AVRGCC. you can download it free from the files section(FILE-AVRBOOK.RAR) of yahoo group-booksbybibin http://groups.yahoo.com/group/booksbybibin/ comments about this book on www.booksbybibin.blogspot.com Here Lm35 is connected to ADC0 if atmega32 and 7segments are connected in PORTB. Internal voltage reference of 2.56 volt is used. The capacitor should be proper to avoid the noise problem occuring in ADC. This code works for temperature from 0-100 degree. .cseg .org 0x000 rjmp RESET RESET: ldi r16,0xff out $17,r16 out $18,r16 rjmp ADC_INIT ADC_INIT: ldi r16,0b11100000 ; setting AD1,AD0 in ADCL ;internal 2.56 reference,Single ;channel A0 out $07,r16 ;setting ADMUX ldi r16,0b10000101 ;setting control reg. ck/32 out $06,r16 ;setting ADCSRA rjmp ADCSTART ADCSTART: sbi $06,6 WAIT: sbis $06,4 rjmp WAIT in r16,$04;ADCL in r17,$05;ADCH rjmp H2BCD H2BCD: ldi r18,0x00 ;using the above algo(MSD) ldi r19,10 ;for addition of 10 ldi r20,0x10 ;for multiplication SUBTRACTION: inc r18 subi r17,10 brmi OUTPUT ;checking if result is negative rjmp SUBTRACTION OUTPUT: add r17,r19 subi r18,1 mul r18,r20 ; instead of shifting MSD add r0,r17 mov r18,r0 out $18,r18 rjmp DELAY DELAY: ; ============================= ; delay loop generator ; 8000000 cycles: ; ----------------------------- ; delaying 7999992 cycles: ldi R20, $48 WGLOOP0: ldi R21, $BC WGLOOP1: ldi R22, $C4 WGLOOP2: dec R22 brne WGLOOP2 dec R21 brne WGLOOP1 dec R20 brne WGLOOP0 ; ----------------------------- ; delaying 6 cycles: ldi R20, $02 WGLOOP3: dec R20 brne WGLOOP3 ; ----------------------------- ; delaying 2 cycles: nop nop ; ============================= rjmp ADCSTART