MODULE main
        PUBLIC main
        SECTION `.text`:CODE:NOROOT(2)
        THUMB
main:
        //inicializaicja ledic
        ldr r0, =0x40023830     // AHB1 clocks
        ldr r1, =0x9     // GPIOD clock
        str r1,[r0]

        ldr r0, =0x40020C00     // GPIOD
        ldr r1, =0x55555555     // out (all)
        str r1, [r0, #0x00]      // MODER
        ldr r1, =0x0            // push-pull
        str r1, [r0, #0x04]      // OTYPER
        ldr r1, =0x0            // low speed
        str r1, [r0, #0x08]      // SPEEDR
        ldr r1, =0x0            // no pull
        str r1, [r0, #0x0C]      // PUPDR
        //konec inicializacije ledic

        //inicializacija gumba
        ldr r0, =0x40020000     // mode
        ldr r1, =0xA8000000     // in
        str r1,[r0]

        ldr r0, =0x4002000C     //
        ldr r1, =0x64000000     //
        str r1,[r0]
        //konec inicializacije gumba

    /*
    // Priziganje in ugasanje ledic v krogu
        ldr r0,=0x40020C00
        ldr r1,=0x8000  // 8000 prizge eno lucko, F000 prizge vse lucke
        ldr r2,=0x4000  // 8000 prizge eno lucko, F000 prizge vse lucke
        ldr r3,=0x2000  // 8000 prizge eno lucko, F000 prizge vse lucke
        ldr r4,=0x1000  // 8000 prizge eno lucko, F000 prizge vse lucke

        strh r1,[r0,#0x18] //prizgemo led
        bl delay
        strh r2,[r0,#0x18] //prizgemo led
        bl delay
        strh r3,[r0,#0x18] //prizgemo led
        bl delay
        strh r4,[r0,#0x18] //prizgemo led
        bl delay

        strh r4,[r0,#0x1A] //ugasnemo led
        bl delay
        strh r3,[r0,#0x1A] //ugasnemo led
        bl delay
        strh r2,[r0,#0x1A] //ugasnemo led
        bl delay
        strh r1,[r0,#0x1A] //ugasnemo led
        bl delay
    */

 loop2:
    // vstopna tocka
        push {lr}
        push {r11}
        mov r11, sp
        ldr r0,=0x40020C00
    ldr r1,=0x40020010      // stanje gumba preberes na bitu 0
        push {r6-r7}

//loop2:
    ldr r2, [r1]    // vrednost, ki je na lokaciji, ki je zapisana v r1, shranis v r2
    ands r2, r2, #1
    it ne
    blne gumb       // ce je zadnji bit postavljen na 1, skoci na labelo gumb

        // izstopna tocka
        pop {r6-r7}
        mov sp, r11
        pop r11
        pop lr
        b loop2

//loop:   b loop

delay:  ldr r5,=0x989680
delay_l:
        subs r5,r5,#1
        bne delay_l
        bx lr

gumb:
    bl delay
    ldr r6,=0xF000
    strh r6,[r0,#0x18]      // prizgem vse lucke
    bl delay
    strh r6,[r0,#0x1A]      // ugasnem vse lucke
    bl delay
    bx lr

    END