;********************************************************************************************************
;                                               uC/OS-II
;                                         The Real-Time Kernel
;
;                                          68HC08 Specific code
;
; File : OS_CPU_A.ASM
; By   : Kerby Suhre
;********************************************************************************************************

    xdef   OSStartHighRdy
    xdef   OSCtxSw
    xdef   OSIntCtxSw

    xref   OSIntExit
    xref   OSIntNesting  
    xref   OSPrioCur    
    xref   OSPrioHighRdy
    xref   OSRunning   
    xref   OSTaskSwHook 
    xref   OSTCBCur     
    xref   OSTCBHighRdy 
    xref   OSTimeTick

;MY_ROM: SECTION

OSStartHighRdy:

    jsr    OSTaskSwHook               
    lda    OSRunning                  
	inca
    sta    OSRunning
    ldx    OSTCBHighRdy               
    stx    OSTCBCur
	pshx
    ldx    OSTCBHighRdy+1
    stx    OSTCBCur+1
	pulh
    lda    0,x                        
	psha
	ldx	   1,x
	pulh
	txs
	pulh							  
    rti                               

OSIntCtxSw:
    ais	   #4                         
	bra	   OSIntCtxSwRtn              
	
OSCtxSw:  
	pshh							  
OSIntCtxSwRtn:
	tsx
	pshx
	pshh
    ldx    OSTCBCur                   
	pshx
    ldx    OSTCBCur+1                
	pulh
	pula
    sta    0,x                         
	pula
	sta	   1,x
    jsr    OSTaskSwHook               
    lda    OSPrioHighRdy              
    sta    OSPrioCur                                                
    ldx    OSTCBHighRdy               
    stx    OSTCBCur
	pshx
    ldx    OSTCBHighRdy+1
    stx    OSTCBCur+1
	pulh
    lda    0,x                         
	psha
	ldx	   1,x
	pulh
	txs
	pulh							   
    rti