; Registers TODO: use .def for these!!!!
;   r16: ISR setup (vct) -> timer0_set (main) -> START_BLINK (loop)
;   r17: timer1_set (main) -> timer1_cnt low byte (loop)
;   r18: timer1_set (main) -> timer1_cnt high byte (loop)
;   r19:
;   r20:


.org 0x0000                 ; RESET Vector
    rjmp    main
.org 0x0002                 ; INT0 button interrupt (tap tempo)
    ;rjump tap_tempo --> should have timer0_start --> if timer0_overflow_count=0 start timer (?)
.org 0x0004                 ; TIMER0 overflow
    rjump timer0_isr
.org 0x0006                 ; TIMER1_COMPA
    rjmp    timer1_isr
.org 0x0012                 ; TIMER0_COMPA
    rjmp    stop_blink

.dseg
    timer0_overflow_count: .byte 1

.cseg
    clr     r0
    sts     timer0_overflow_count,  r0


#define __SFR_OFFSET 0
#include <avr/io.h>

#include "led.inc"
#include "timer.inc"
;#include "bpm.inc"
;#include "midi.inc"

.global main

main:
    ldi         r16,        lo8(RAMEND)
    out         SPL,        r0          ; Setup stack pointer LOW
    ldi         r16,        hi8(RAMEND)
    out         SPH,        r0          ; Setup stack pointer HIGH

    sei                                 ; Global interrupt flag

    ;cbi        DDRB,       PB1         ; Set EC11 clockwise on PB5 as input
    ;cbi        DDRB,       PB2         ; Set EC11 counter-clockwise on PB3 as input
    ;cbi        DDRB,       PB5         ; Set EC11 button (555 square wave) on PB4 as input
    sbi         DDRB,       PB0         ; Set led on PB0 as output
    ;ldi         r26,        60          ; Default BPM //TODO: save to eeprom not register, on runtime also ldi on r24 register

    rcall       timer0_set
    ;rcall       timer1_set


; loop: calculate tempo (high priority!) and save, led blinking, segment led writing
loop:
    ;ldi         r24,        30          ; Load current BPM to register //NOTE: hardcoded temporary
                                        ; TODO: compare two registers (current bpm and previous bpm)
    ;rcall       tempo_calc              ; CHANGE: if BPM changed then rcall BPM calculation function else skip because ticks tempo is the value already in [OCR1C]
                                        ; if this BPM != previous BPM then load this to another register (will be used as the 'previous register')

    ; final result stored in OCR1C as ticks

    ; TODO: look if there are alternatives to rcall

    ;rcall      midi_send       ; Send MIDI ping


    ; if midi clock then after do:
    ; SOME CPI HERE
    brne        segment_led
    START_BLINK                         ; Macro for inlining blink start logic

    rjmp      segment_led               ; Output current BPM to 3-digit 7-segment LED [r24]


    ; sleep when BPM is stabilized (whenever BPM calculation are not being done) and outside of midi send
    ; to do this explore MCUCR register, it can do a lot of stuff

    rjmp        loop

; TODO: move to separate file
; keep as subroutine as it's called in two parts in the code
; or it can create issues with compiler
segment_led:
    rjmp        loop