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Reorganized folders, added pal-adapter io device folder

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Daniele Verducci su MatissePenguin
2021-01-02 16:33:51 +01:00
parent 55f5d62082
commit 68752e85a7
35 changed files with 327 additions and 1 deletions
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pat80-io-devices/composite-pal-adapter/software/avr-assembly/main.asm Normal file
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.include "atmega1284definition.asm"
; define constant
.equ LED_PIN = PD7 ; use PD7 as LED pin
; start vector
.org 0x0000
rjmp main ; jump to main label
; main program
main:
sbi DDRD, LED_PIN ; set LED pin as output
loop:
sbic PIND, LED_PIN ; if bit of LED pin is clear, skip next line
cbi PORTD, LED_PIN ; if 1, turn the LED off
sbis PIND, LED_PIN ; if bit of LED pin is set, skip next line
sbi PORTD, LED_PIN ; if 0, light the LED up
delay_500ms:
ldi r20, 32 ; set register, r20 = 32
delay2:
ldi r19, 64 ; set register, r19 = 64
delay1:
ldi r18, 128 ; set register, r18 = 128
delay0:
dec r18 ; decrement register, r18 = r18 - 1
brne delay0 ; if r18 != 0, jump to label delay0
dec r19 ; decrement register, r19 = r19 -1
brne delay1 ; if r19 != 0, jump to label delay1
dec r20 ; decrement register, r20 = r20 -1
brne delay2 ; if r20 != 0, jump to label delay2
rjmp loop ; if r20 == 0, jump to label loop