main.asm

.include "m32def.inc"
jmp reset
jmp reset
jmp reset
jmp reset
jmp reset
jmp reset
jmp reset
jmp passed_3sec
jmp reset
jmp reset
jmp reset
jmp reset
jmp reset
jmp reset
jmp reset
jmp reset
jmp reset
jmp reset
jmp reset
jmp reset
jmp reset
reset:
ldi r16, high(RAMEND)
out SPH, r16
ldi r16, low(RAMEND)
out SPL, r16

ldi r16, 0xFF
out DDRA, r16 ;port a is output
ldi r17, 0x00
out PORTA, r17 ;leds off

main:
cli                  ;interrups dezactivated
ldi r16, 0b00001000  ;configuring USART:
out UCSRB, r16       ;300bps, 8bit, even parity, 2 bit stop
ldi r16, 0b10101110
out UCSRC, r16
ldi r16, 0x06        ;setting baud rate for 8Mhz
out UBRRH, r16       
ldi r16, 0x81
out UBRRL, r16
ldi r16, 0b00000000  ;seting timer counter1
out TCCR1A, r16      ;mode CTC
in r16, TIMSK
andi r16, 0b11010011 
ori r16, 0b00010000  
out TIMSK, r16       
                     
ldi r16, 0x5B        ; 0x5B8E = 23438
out OCR1AH, r16      ;23438 * 1/(8mhz/1024) ~= 3s
ldi r16, 0x8E
out OCR1AL, r16
ldi r16, 0b00001101  ;start timer
out TCCR1B, r16      
sei                  ;activate interrups
bucla:
rjmp bucla

passed_3sec:
in r20, SREG
ldi r16, 0b00010000
out PORTA, r16    ;led on

ldi r16, 0x6C     ;ascii for "l"
out UDR, r16
call wait         ;wait for data to be sent

ldi r16, 0x61     ;ascii for "a"
out UDR, r16
call wait         

ldi r16, 0x62     ;ascii for "b"
out UDR, r16
call wait         

ldi r16, 0x20     ;ascii for " "(SPACE)
out UDR, r16
call wait         

ldi r16, 0x6D     ;ascii for "m"
out UDR, r16
call wait         

ldi r16, 0x69     ;ascii for "i"
out UDR, r16
call wait         

ldi r16, 0x63     ;ascii for "c"
out UDR, r16
call wait        

ldi r16, 0x72     ;ascii for "r"
out UDR, r16
call wait        

ldi r16, 0x6F     ;ascii for "o"
out UDR, r16
call wait         


ldi r16, 0x00
out PORTA, r16    ;led off
out SREG, r20     
reti              ;return from interrupt

wait:
in r16, UCSRA     ;read the state of UCSRA
sbrs r16, UDRE    ;check if UDRE is empty
rjmp wait         ;UDRE is not empty, we wait more
ret               ;UDRE is empty, we return from waiting