.equ ADDR_JP1, 0x10000060    /* Address GPIO JP1*/
  .equ PERIOD, 0xa
  .global main
  
 main:
   movia  r8, ADDR_JP1
   movia  r10, 0x07f557ff      /* set direction for motors and sensors to output and sensor data register to inputs*/
   stwio  r10, 4(r8)
      
 LOOP0:
   movia  r11, 0xfffffbff      /* enable sensor 0, disable all motors*/
   stwio  r11, 0(r8)
   ldwio  r5,  0(r8)           /* checking for valid data sensor 0*/
   srli   r5,  r5,11           /* bit 11 equals valid bit for sensor 0*/           
   andi   r5,  r5,0x1		   /* check if the valid bit is 0 or 1*/
   cmpeqi r6,  r5,0x1
   beq    r0,  r6,SEN0         /* checking if low indicated polling data at sensor 0 is valid*/
   br     LOOP0

 LOOP4:
   movia  r11, 0xfffeffff      /* enable sensor 4, disable all motors*/
   stwio  r11, 0(r8)
   ldwio  r5,  0(r8)           /* checking for valid data sensor 4*/
   srli   r5,  r5,17           /* bit 19 equals valid bit for sensor 4*/           
   andi   r5,  r5,0x1		   /* check if the valid bit is 0 or 1*/
   cmpeqi r6,  r5,0x1
   beq    r0,  r6,SEN4         /* checking if low indicated polling data at sensor 4 is valid*/
   br     LOOP4
 
 SEN0:
   ldwio  r10, 0(r8)         /* read sensor 0 value (into r10) */
   srli   r10, r10, 27       /* shift to the right by 27 bits so that 4-bit sensor value is in lower 4 bits */
   movi   r3,0x14          
   ble 	  r10, r3, MOTCNW	 /* if sensor 0 has a value less than 3 then move clockwise*/
   br	  LOOP4
   
 SEN4:
   ldwio  r10, 0(r8)         /* read sensor 4 value (into r10) */
   srli   r10, r10, 27       /* shift to the right by 27 bits so that 4-bit sensor value is in lower 4 bits */
   movi   r5,0x15         
   ble 	  r10, r5, MOTCW	 /* if sensor 4 has a value less than 5 then move counter clockwise*/
   br	  LOOP0
   
 MOTCW:
   movia  r9, 0xfffffffc       /* motor0 enabled (bit0=0), direction set to forward (bit1=0) */
   stwio  r9, 0(r8)
   br TIMER
   
 MOTCNW:
   movia  r9, 0xfffffffe       /* motor0 enabled (bit0=0), direction set to reverse (bit1=0) */
   stwio  r9, 0(r8)
   br TIMER
   
 TIMER:
  movia r7, 0x10002000                   /* r7 contains the base address for the timer */
  stwio r0, 0(r7)
  movui r2, 100
  stwio r2, 8(r7)                          /* Set the period to be 1000 clock cycles */
  stwio r0, 12(r7)
  movui r2, 4
  stwio r2, 4(r7)                          /* Start the timer without continuing or interrupts */
  br TIMERCHK

 TIMERCHK:
  movia r7, 0x10002000         /* r7 contains the base address for the timer */
  movi r6, 1
  ldwio r3, 0(r7) 
  bne r3,r6, TIMERCHK
  movi r4,1000
  call TIMER2
  br LOOP0
  
 TIMER2:
  movia r7, 0x10002000                   /* r7 contains the base address for the timer */
  movia  r11, 0xffffffff                 /* enable sensor 0, disable all motors*/
  stwio r0, 0(r7)
  mov r2, r4
  stwio r2, 8(r7)                          /* Set the period to be 1000 clock cycles */
  stwio r0, 12(r7)
  movui r2, 4
  stwio r2, 4(r7)                          /* Start the timer without continuing or interrupts */
  br TIMERCHK2

 TIMERCHK2:
  movia r7, 0x10002000         /* r7 contains the base address for the timer */
  movi r6, 1
  ldwio r3, 0(r7) 
  bne r3,r6, TIMERCHK2
  ret 
	
	
	
	
#BY FATROCK
#thanks