; rgb_mali.asm
;
; 3 leds (red, green, blue) on different ports.
; cm mode: continuous mixed colors
; rgb mode: keep one special color
;
; modes switchable by uart
;
; author: hackbard@hackdaworld.dyndns.org


.include "../include/2313def.inc"

; defines & equals
.def zero = r0
.def one = r1
.def countrgb = r2
.def desc = r3
.equ RUP = 0
.equ RDOWN = 1
.equ GUP = 2
.equ GDOWN = 3
.equ BUP = 4
.equ BDOWN = 5
.def tmp = r16
.def uart_count = r17
.def count = r18
.def RED = r19
.def GREEN = r20
.def BLUE = r21
.def mode = r22
.equ cm = 0
.equ rgb = 1
.def OUTR = r23
.def FULLR = r24
.def tmp2 = r25
.equ LED_R = PD2
.equ LED_G = PD3
.equ LED_B = PD4
.equ LED_PORT = PORTD
.equ CM1 = 85
.equ CM2 = 170

;
; interrupt voctors
;
; reset
rjmp INIT
; int0
reti
; int1
reti
; timer/counter capt 1
reti
; timer/counter compare
reti
; timer/counter overflow 1
rjmp DO_IT
; timer/counter overflow 0
reti
; uart rx complete
rjmp UART_RECEIVE
; uart data register empty
reti
; uart tx complete
reti
; analog comparator
reti

;
; init routine
;
INIT:
; alloc stack pointer
ldi r16,low(RAMEND)
out SPL,r16
; timer: clock/8
ldi tmp,((1<<CS11))
out TCCR1B,tmp
; enable timer overflow interrupt
ldi tmp,(1<<TOIE1)
out TIMSK,tmp
; enable uart + rx complete interrupt
ldi tmp,51 ; 9600 baud, 0,2% error @ 8mhz
out UBRR,tmp
ldi tmp,((1<<RXCIE)|(1<<RXEN)|(1<<TXEN))
out UCR,tmp
; init registers
ldi tmp,1
mov one,tmp
ldi tmp,0
mov zero,tmp
mov countrgb,tmp
ldi uart_count,0
ldi count,0
ldi RED,CM2
ldi GREEN,0x0
ldi BLUE,0x0
; led pins are outputs
ldi tmp,((1<<LED_R)|(1<<LED_G)|(1<<LED_B))
out DDRD,tmp
; default mode: cm
ldi mode,cm
; enable interrupts (global)
sei
; jump to main
rjmp MAIN

;
; decide what to do
;
DO_IT:
cpi mode,cm
breq CM_ACTION
reti

;
; specify action
;


;
; continuous mode action
;
CM_ACTION:
cp countrgb,zero
breq RD_GU
ldi tmp,CM1
cp countrgb,tmp
breq GD_BU
ldi tmp,CM2
cp countrgb,tmp
breq BD_RU
ldi tmp,255
cp countrgb,tmp
breq RESET_RGB
rjmp MAKE_RGB

;
; reset rgb
;
RESET_RGB:
ldi RED,CM2
mov GREEN,zero
mov BLUE,zero
mov desc,zero
rjmp MAKE_RGB

;
; set desc
;
RD_GU:
ldi tmp,((1<<RDOWN)|(1<<GUP))
mov desc,tmp
rjmp MAKE_RGB
GD_BU:
ldi tmp,((1<<GDOWN)|(1<<BUP))
mov desc,tmp
rjmp MAKE_RGB
BD_RU:
ldi tmp,((1<<BDOWN)|(1<<RUP))
mov desc,tmp
rjmp MAKE_RGB

;
; do the actual rgb calculation
;
MAKE_RGB:
ldi tmp,(1<<RUP)
and tmp,desc
add tmp,tmp
add RED,tmp
ldi tmp,(1<<GUP)
and tmp,desc
lsr tmp
lsr tmp
add tmp,tmp
add GREEN,tmp
ldi tmp,(1<<BUP)
and tmp,desc
lsr tmp
lsr tmp
lsr tmp
lsr tmp
add tmp,tmp
add BLUE,tmp
ldi tmp,(1<<RDOWN)
and tmp,desc
lsr tmp
add tmp,tmp
sub RED,tmp
ldi tmp,(1<<GDOWN)
and tmp,desc
lsr tmp
lsr tmp
lsr tmp
add tmp,tmp
sub GREEN,tmp
ldi tmp,(1<<BDOWN)
and tmp,desc
lsr tmp
lsr tmp
lsr tmp
lsr tmp
lsr tmp
add tmp,tmp
sub BLUE,tmp
add countrgb,one
reti

;
; main routine
;
MAIN:
; jump to main loop
rjmp LOOP

:
; main loop
;
LOOP:
; reset lights if loop starts 
cpi count,0
breq RESET_LEDS
; now check leds
rjmp CHECK_RED

;
; reset leds
;
RESET_LEDS:
ldi OUTR,((1<<LED_R)|(1<<LED_G)|(1<<LED_B))
rjmp CHECK_RED

;
; check red + jump to green check
;
CHECK_RED:
cp count,RED
breq SWITCH_OFF_R
rjmp CHECK_GREEN

;
; switch of red led
;
SWITCH_OFF_R:
subi OUTR,(1<<LED_R)
rjmp CHECK_GREEN

;
; check green + jump to blue check
;
CHECK_GREEN:
cp count,GREEN
breq SWITCH_OFF_G
rjmp CHECK_BLUE

;
; switch of green led
;
SWITCH_OFF_G:
subi OUTR,(1<<LED_G)
rjmp CHECK_BLUE

;
; check blue + "do the light"
;
CHECK_BLUE:
cp count,BLUE
breq SWITCH_OFF_B
rjmp LIGHT

;
; switch of blue led
;
SWITCH_OFF_B:
subi OUTR,(1<<LED_B)
rjmp LIGHT

;
; light it up
;
LIGHT:
ldi FULLR,0xff
eor FULLR,OUTR
out LED_PORT,FULLR
rjmp INC_COUNT

;
; increase counter + jump back to main loop
;
INC_COUNT:
add count,one
rjmp LOOP

;
; receive from uart
;
UART_RECEIVE:
cp uart_count,zero
breq GET_MODE
cpi uart_count,1
breq GET_R_VALUE
cpi uart_count,2
breq GET_G_VALUE
cpi uart_count,3
breq GET_B_VALUE

;
; get mode
;
GET_MODE:
in tmp,UDR
cpi tmp,0x63 ; 0x63 = 'c'
breq SET_CONTINUOUS_MODE
cpi tmp,0x73 ; 0x73 = 's'
breq SET_SPECIFY_MODE
ldi uart_count,0
reti

;
; set cmode
;
SET_CONTINUOUS_MODE:
ldi mode,cm
ldi uart_count,0
reti

;
; set specify mode
;
SET_SPECIFY_MODE:
ldi mode,rgb
add uart_count,one
; check
out UDR,mode
reti

;
; get red value
;
GET_R_VALUE:
in RED,UDR
add uart_count,one
; check
out UDR,RED
reti

;
; get green value
;
GET_G_VALUE:
in GREEN,UDR
add uart_count,one
; check
out UDR,GREEN
reti

;
; get blue value
;
GET_B_VALUE:
in BLUE,UDR
mov uart_count,zero
; check
out UDR,BLUE
reti