.include "m8def.inc"

.def A         = r16
.def B         = r17
.def Steptime1 = r19
.def Steptime2 = r20
.def Stepcount1= r21
.def Stepcount2= r22
.def Stepsave1 = r23
.def Stepsave2 = r24

.org 0x0000
rjmp Start
.org 0x0004
rjmp Motor1
.org 0x0009
rjmp Motor2

Start:

	 ldi   A,0b11111111
         out   ddrd,A
	 ldi   A,0b11111111
	 out   ddrb,A
 														
	 ldi A, HIGH(RAMEND)        
         out SPH,A
         ldi A, LOW(RAMEND)             
         out SPL,A
 
         ldi     A, (1<<TOIE0)|(1<<TOIE2) 
         out     TIMSK, A

Main:    	  	
	  ldi Steptime1,100 	    ;Frequenz Motor schnell
	  mov Stepsave1,Steptime1   
	  ldi Steptime2,200         ;Frequenz Motor langsam
	  mov Stepsave2,Steptime2


Timeran:  ldi   A, 0b00000010 
	  ldi   B, 0b00000010   
	  out   TCCR0, A
	  out	TCCR2, B
	  sei                               
  	  rjmp ende


ende: rjmp ende


Motor1:  dec Steptime1                ;Stepfrequenz einhalten
	 	 brne StillDelay1 
	 	 push A
	 	 push B
	 	 in A,SREG
	 	 push A

M1Step1: cpi StepCount1,1             ;Schrittposition korrekt?
		 brne M1Step2

	 	 ldi   B,0b11000000   ;Schritt initialisieren

	 	 rjmp  IncStepCount1

M1Step2: cpi StepCount1,2
		 brne M1Step3

		 ldi   B,0b01100000

	 	 rjmp  IncStepCount1

M1Step3: cpi StepCount1,3
		 brne M1Step4

		 ldi   B,0b00110000

	 	 rjmp  IncStepCount1

M1Step4: cpi StepCount1,4
		 brne M1Step1

		 ldi   B,0b10010000

	 	 rjmp  ClearStepCount1


ClearStepCount1:	
	   	 ldi   Stepcount1,1  ;Schrittposition (1-4) speichern
	 	 rjmp  Motor1end

StillDelay1:
reti

IncStepCount1:				
inc Stepcount1			     ;Schrittposition (1-4) speichern
rjmp Motor1end
	  
Motor1end:
	out portd,B                  ;Schritt ausführen
	mov   Steptime1,Stepsave1    ;Zeit für Schrittfrequenz erneut laden
	pop   A                     
	out   SREG,A
	pop   B
	pop   A
	reti




Motor2:   dec  Steptime2
	  brne StillDelay2
	  push A
	  push B
	  in A,SREG
	  push A

M2Step1: cpi StepCount2,1     ;Schrittposition korrekt?
		 brne M2Step2

		 ldi   B,0b00100111

	 	 rjmp  IncStepCount2

M2Step2: cpi StepCount2,2    
		 brne M2Step3

		 ldi   B,0b00110011

	 	 rjmp  IncStepCount2

M2Step3: cpi StepCount2,3    
		 brne M2Step4

		 ldi   B,0b00011011

	 	 rjmp  IncStepCount2

M2Step4: cpi StepCount2,4    
		 brne M2Step1

	 	 ldi   B,0b00001111

	 	 rjmp  ClearStepCount2


ClearStepCount2:	
		ldi   Stepcount2,1
		rjmp  Motor2end

StillDelay2:
	reti
	  
IncStepCount2:
	inc Stepcount2
	rjmp Motor2end

Motor2end:
	out  portb,B	
	mov   Steptime2,Stepsave2
	pop   A
	out   SREG,A
	pop   B
	pop   A    
	reti