A2osX/SYS/KERNEL.S.IRQ.txt

PR#3
PREFIX /A2OSX.BUILD
LOMEM $A00
INC 1
AUTO 6
*--------------------------------------
* called directly by IRQ Vector $FFFE in AuxLC
* Must keep:
*  A,X,Y
*   SETREADAUX
*  if we are here, Aux ZP/Stack already On
* Exit with RTI
* if A2osX Drivers cannot clear IRQ, 
* must call regular System Handler
*--------------------------------------
K.IrqHandlerAuxLC
				sta K.IrqMgr.A
				pla
				pha
				and #$10				BRK?
				beq .10
				bra *
				lda K.IrqMgr.A
.82				jmp (K.IrqMgrOldFFFE)
				
.10				stx	K.IrqMgr.X
				sty K.IrqMgr.Y
				lda $fe
				pha
				lda $ff
				pha
				lda RDREADAUX
				pha
				sta CLRREADAUX			Make sure we can access DevMgr.Table
				
				jsr K.IrqHandler
					
				pla						Must keep Carry
				bpl .81
				sta SETREADAUX
.81				pla
				sta $ff
				pla
				sta $fe
				ldy K.IrqMgr.Y
				ldx K.IrqMgr.X
				lda K.IrqMgr.A
				bcs .82
				rti
*--------------------------------------
K.IrqMgrOldFFFE	.BS 2
K.IrqMgr.A		.BS 1
K.IrqMgr.X		.BS 1
K.IrqMgr.Y		.BS 1
K.IrkMgr.VBL	.BS 1
K.IrkMgr.VBLINT	.BS 1
*--------------------------------------
* Called by :
* Kernel IrqHandlerAuxLC
* ProDOS IRQ Manager (GP)
*--------------------------------------
K.IrqHandler	lda K.IrkMgr.VBL
				beq .10					0, totally disabled....

				jsr K.IrqMgrVBL.MSM		SERVEMOUSE
				bcs .10					Not From Mouse
				
				ldx K.IrqMgrVBL.0n
				lda $778,x
				and #$08				IRQ was caused by VBL ?
				beq .10
				
				ldx K.IrqMgrVBL.MRM+2	$Cn
				ldy K.IrqMgrVBL.n0
				jsr K.IrqMgrVBL.MRM		READMOUSE
				
				inc K.IrkMgr.VBLINT
				
				lda SYS.BASL0+37
				eor #'V'
				sta SYS.BASL0+37		Confirm VBL signal valid for EvtMgr
				
				clc
				rts
				
.10				>LDYAI DevMgr.Table
				>STYA $fe

				ldx DevMgr.Count
				
.4				ldy #S.DEV.S
				lda ($fe),y
				and #S.DEV.S.IRQ
				beq .6
				
				phx
				jsr K.IrqHandlerJMP
				plx
				bcc .8					CC, IRQ cleared by device
				
.6				lda $fe
				clc
				adc #S.DEV
				sta $fe
				bcc .7
				inc $ff
				
.7				dex
				bne .4
				
				sec
				
.8				rts
*--------------------------------------
K.IrqMgrVBL.n0	.BS 1
K.IrqMgrVBL.0n	.BS 1
K.IrqMgrVBL.MSM	jmp $0000
K.IrqMgrVBL.MRM	jmp $0000
*--------------------------------------
K.IrqHandlerJMP	ldx #DEVMGR.IRQ
				jmp ($fe)
*--------------------------------------
MAN
SAVE /A2OSX.SRC/SYS/KERNEL.S.IRQ
LOAD /A2OSX.SRC/SYS/KERNEL.S
ASM