behajici ledka, SPS, fixed

/*.include "nios_macros.s"*/
.equ LEDR_BASE, 0x10000000
.equ SW_BASE, 0x10000040
.equ LED_COUNT, 17
.equ LAST_DRAM_WORD, 0x7FFFFC

.text                           /* executable code follows */
    .global _start
_start:
    /* initialize base addresses of parallel ports */
    movia       r10, SW_BASE        /* SW slider switch base address */
    movia       r12, LEDR_BASE      /* red LED base address */
    movia       sp, LAST_DRAM_WORD
    movia       r2, 1
    movia       r5, 1 /* start led position */
    movia       r6, 0 /* smer */
    movia       r15, 0  /* porovnavac ledky vs switche*/
    movia       r16, LED_COUNT
    movia       r17, LED_COUNT

LOOP:
    ldwio       r7, 0(r10) /* load switches*/
    stwio       r5, 0(r12) /*ulozeni do ledek*/

    call        WAITING

    beq         r6, r0, LEFT
    beq         r6, r2, RIGHT
    br          LOOP

RIGHT:
    roli        r5, r5, 31 /* posun ledky doprava*/
    addi        r16, r16,1 /* ledka o jednu vyssi*/
    and         r15, r7, r5 /* pokud je ledka nad sepnutym switchem bude vysledek nenulovy*/
    beq         r16, r17, MOVELEFT /* pokud na okraji zmen smer*/
    bne         r15, r0, MOVELEFT /*pokud nad switchem zmen smer*/
    br          LOOP

LEFT:
    roli        r5, r5, 1 /* posun ledky doleva*/
    addi        r16, r16,-1 /* ledka o jednu nizsi*/
    and         r15, r7, r5 /* pokud je ledka nad sepnutym switchem bude vysledek nenulovy*/
    beq         r16, r0, MOVERIGHT /* pokud na okraji zmen smer*/
    bne         r15, r0, MOVERIGHT /*pokud nad switchem zmen smer*/
    br          LOOP

MOVELEFT:
    movia       r6, 0
    br          LOOP

MOVERIGHT:
    movia       r6, 1
    br          LOOP

 WAITING:
    stw         r18,0(sp)
    addi        sp, sp, -4
    movia       r18, 10000000

WAIT1:
    addi        r18, r18, -1
    bne         r18, r0, WAIT1
    addi        sp, sp, 4
    ldw         r18,0(sp)
    ret

.end