X-Git-Url: https://www.hackdaworld.org/gitweb/?a=blobdiff_plain;f=beginners%2Flight_control.asm;fp=beginners%2Flight_control.asm;h=432ca7d97751bed4670d8188e490a0af66d63850;hb=b966394e758f0b6c51c5a41bfc1177d8c4fc2529;hp=0000000000000000000000000000000000000000;hpb=437e9534e0baad7c82ab485791bc2fa30e536389;p=my-code%2Fatmel.git

diff --git a/beginners/light_control.asm b/beginners/light_control.asm
new file mode 100644
index 0000000..432ca7d
--- /dev/null
+++ b/beginners/light_control.asm
@@ -0,0 +1,100 @@
+;
+; control the light connected to the pwm output pins
+;
+; author: hackbard@hackdaworld.org
+;
+
+; specify device
+.include "../include/2313def.inc"
+
+; ------------------
+; interrupt vectors:
+; ------------------
+
+; reset
+rjmp RESET
+; int0
+reti
+; int1
+reti
+; timer 1 capture
+reti
+; timer 1 compare
+reti
+; timer 1 overflow
+reti
+; timer 0 overflow
+reti
+; usart rx complete
+rjmp UART_RX
+; usart data register empty
+reti
+; usart tx complete
+reti
+; analog comperator
+reti
+; pin change interrupt
+reti
+; timer/counter 1 compare match b
+reti
+; timer/counter 0 compare match a
+reti
+; timer/counter 0 compare match b
+reti
+; usi start condition
+reti
+; usi overflow
+reti
+; eeprom ready
+reti
+; watchdog timer overflow
+reti
+
+; -----
+; code:
+; -----
+
+RESET:
+	; set stackpointer
+	ldi r16,low(RAMEND)	; write top of ramend (lowbyte)
+	out SPL,r16		; to stackpointer
+
+	; rs232 init
+	ldi r16,12 	; "38.4k bps @ 8 mhz" in r16
+	out UBRR,r16 	; write to uart baudrate register
+	ldi r16,(1<<RXEN)|(1<<TXEN)|(1<<RXCIE)	; enable rx/tx + rx interrupt
+	out UCSRB,r16	; write to uart control register
+
+	; pwm (OC0A=PB2 OC0B=PD5)
+	; set as output
+	ldi r16,(1<<DDB2)
+	out DDRB,r16
+	ldi r16,(1<<DDD5)
+	out DDRD,r16
+	; output 0
+	ldi r16,(1<<PINB2)
+	subi r16,0xff
+	out PORTB,r16
+	ldi r16,(1<<PIND5)|(1<<PIND6)
+	subi r16,0xff
+	out PORTD,r16
+	; toggle OC0A/B on compare match / fast pwm
+	ldi r16,(1<<COM0A0)|(1<<COM0B0)|(1<<WGM00)|(1<<WGM01)
+	out TCCR0A,r16
+	; top in OCR0A / no clock prescaling
+	ldi r16,(1<<WGM02)|(1<<CS00)
+	; overflow interrupt enable
+	
+	; initial pwm value 0x7f
+	ldi r16,0x7f
+	out OCR0A,r16
+	out OCR0B,r16
+
+	; global interrupt enable
+	sei
+
+MAIN:
+	rjmp MAIN
+
+UART_RX:
+	reti