OPT c+,l-,o+

*********************
*                   *
*  BootNTSC 1.0     *
*                   *
*  by Nico François *
*********************

	incdir "INCLUDE:"
	include "exec/types.i"
	include "exec/execbase.i"
	include "exec/memory.i"
	include "exec/resident.i"
	include "exec/exec_lib.i"
	include "graphics/gfxbase.i"
	include "graphics/graphics_lib.i"
	include "libraries/dos_lib.i"

NULL	equ	0

	movem.l d0/a0,-(a7)
	move.l ($4).w,a6
	lea DosName(PC),a1
	jsr _LVOOldOpenLibrary(a6)				; open DOS
	lea DOSBase(PC),a1
	move.l d0,(a1)
	move.l d0,a6
	jsr _LVOOutput(a6)						; get stdout
	lea stdout(PC),a1
	move.l d0,(a1)
	lea header.txt(PC),a0					; print header to console
	move.l #header.len,d3
	bsr puts

	move.w $DFF004,d0							; check for new 1Mb Agnus
	and.w #$2000,d0
	bne.s ok1MbAgnus
	addq.w #8,a7
	lea oldagnus.txt(PC),a0					; if not available print
	move.l #oldagnus.len,d3					; message
	move.l ($4).w,a6
	bra putsandexit
ok1MbAgnus:
	movem.l (a7)+,d0/a0						; get command line back

	move.l ($4).w,a6
	move.b #0,0(a0,d0.w)						; zero terminated
cmdloop:
	move.b (a0)+,d0							; look for 'I' or 'R'
	beq.s template
	cmp.b #'i',d0
	beq.s install
	cmp.b #'I',d0
	beq.s install
	cmp.b #'r',d0
	beq quit
	cmp.b #'R',d0
	beq quit
	bra.s cmdloop

template:										; print usage line
	lea usage.txt(PC),a0
	move.l #usage.len,d3
	bra putsandexit

install:
	move.l ($4).w,a6
	lea PortName(PC),a1
	jsr _LVOFindPort(a6)						; find our port
	tst.l d0
	beq.s allocit
	lea already.txt(PC),a0					; found, so already installed
	move.l #already.len,d3
	bra putsandexit

allocit:
	move.l #BlockLen,d0
	move.l #MEMF_CHIP,d1						; allocate memory for reset code
	jsr _LVOAllocMem(a6)						; must be in CHIP !!
	tst.l d0
	bne.s memok
	lea nomem.txt(PC),a0						; out of memory ???
	move.l #nomem.len,d3
	bra putsandexit

memok:
	move.l d0,a5								; a5 holds address of copy
	lea StartBlock(PC),a0
	move.l d0,a1
	move.l #BlockLen,d0
	jsr _LVOCopyMem(a6)						; copy block to allocated memory
	move.w #$4000,$DFF09A					; DISABLE
	addq.b #1,IDNestCnt(a6)
	lea RomTagPtrs-StartBlock(a5),a0
	move.l KickTagPtr(a6),4(a0)			; old romtag pointer in array
	beq.s yestag
	bset #7,4(a0)								; set bit if there are more
yestag:
	move.l a0,KickTagPtr(a6)				; pointer to our array
	lea RomTag-StartBlock(a5),a1
	move.l a1,(a0)								; fill in our romtag pointer

	lea myMemList-StartBlock(a5),a1		; init memlist and put in
	move.l a5,ML_SIZE+ME_ADDR(a1)			; KickMemPtr list to protect
	move.l KickMemPtr(a6),d0				; our memory
	move.l d0,LN_SUCC(a1)
	move.l a1,KickMemPtr(a6)
inittag:
	lea RomTag-StartBlock(a5),a1			; init romtag
	move.l a1,RT_MATCHTAG(a1)
	lea RT_SIZE(a1),a2
	move.l a2,RT_ENDSKIP(a1)
	lea TagName-StartBlock(a5),a2
	move.l a2,RT_NAME(a1)
	move.l a5,RT_INIT(a1)
	jsr _LVOSumKickData(a6)					; calculate checksum
	move.l d0,KickCheckSum(a6)
	lea Port-StartBlock(a5),a1				; init and add our port
	moveq #0,d0
	move.l d0,(a1)
	move.l d0,LN_PRED(a1)
	lea PortName-StartBlock(a5),a0
	move.l a0,LN_NAME(a1)
	jsr _LVOAddPort(a6)
	subq.b #1,IDNestCnt(a6)					; ENABLE
	bge.s noenable
	move.w #$C000,$DFF09A
noenable:
	lea installed.txt(PC),a0				; inform user of installation
	move.l #installed.len,d3
	bra.s putsandexit

quit:
	lea PortName(PC),a1						; are we already installed ?
	jsr _LVOFindPort(a6)
	tst.l d0
	bne.s portfound
	lea nohandler.txt(PC),a0				; no, can't quit then
	move.l #nohandler.len,d3
	bra.s putsandexit

portfound:
	move.l d0,a4								; we found our port, so remove it
	move.l a4,a1
	jsr _LVORemPort(a6)

	move.w #$4000,$DFF09A					; DISABLE
	addq.b #1,IDNestCnt(a6)

	lea myMemList-Port(a4),a1				; remove our memlist from
	lea KickMemPtr(a6),a0					; KickMemPtr list.
nextnode:
	move.l LN_SUCC(a0),d0
	cmp.l d0,a1
	beq.s foundmylist
	move.l d0,a0
	bra.s nextnode
foundmylist:
	move.l LN_SUCC(a1),d0
	move.l d0,LN_SUCC(a0)	; LN_SUCC = 0, so this also works for KickMemPtr

	move.l RomTagPtrs-Port+4(a4),KickTagPtr(a6)	; old RomTag back
	beq.s noclr2
	bclr #7,KickCheckSum(a6)
noclr2:
	jsr _LVOSumKickData(a6)					; calculate checksum
	move.l d0,KickCheckSum(a6)
	subq.b #1,IDNestCnt(a6)					; ENABLE
	bge.s noenable2
	move.w #$C000,$DFF09A
noenable2:
	lea StartBlock-Port(a4),a1				; free our copied block
	move.l #BlockLen,d0
	jsr _LVOFreeMem(a6)
	lea removed.txt(PC),a0					; and inform the user
	move.l #removed.len,d3

putsandexit:
	bsr.s puts									; print string in A0, length D3
	move.l DOSBase(PC),a1
	jsr _LVOCloseLibrary(a6)				; close DOS and exit
	moveq #0,d0
	rts

* text-ptr in A0, length in D3
puts:
	move.l a6,-(a7)
	move.l a0,d2
	move.l stdout(PC),d1
	move.l DOSBase(PC),a6
	jsr _LVOWrite(a6)
	move.l (a7)+,a6
	rts

header.txt:
	dc.b $9b,'1mBootNTSC 1.0 ',$9b,'0m',$9b,'33mby Nico François',$9b,'0m',10
header.len equ *-header.txt
oldagnus.txt:
	dc.b 'You haven''t got the ECS 1Mb Agnus, so run out and buy one !',10,0
oldagnus.len equ *-oldagnus.txt
already.txt:
	dc.b 'NTSC RomTag already installed !',10,0
already.len equ *-already.txt
usage.txt:
	dc.b 'Usage: BootNTSC [I=INSTALL|R=REMOVE]',10,0
usage.len equ *-usage.txt
installed.txt:
	dc.b 'NTSC RomTag installed, reset to activate !',10,0
installed.len equ *-installed.txt
nomem.txt:
	dc.b 'No memory for RomTag (I only need about 250 bytes) !?!',10,0
nomem.len equ *-nomem.txt
nohandler.txt:
	dc.b 'NTSC RomTag not installed !',10,0
nohandler.len equ *-nohandler.txt
removed.txt:
	dc.b 'NTSC RomTag removed !',10,0
removed.len equ *-removed.txt
DosName:
	dc.b 'dos.library',0
	EVEN
DOSBase:
	dc.l 0
stdout:
	dc.l 0

*****************************************************************************

StartBlock:										; this is the routine that will
	movem.l d0-d7/a0-a6,-(a7)				; be executed when we reset
	move.l ($4).w,a6

	lea Port(PC),a1							; add our port to the system list
	moveq #0,d0
	move.l d0,(a1)
	move.l d0,LN_PRED(a1)
	lea PortName(PC),a0
	move.l a0,LN_NAME(a1)
	jsr _LVOAddPort(a6)

**** Put AMIGA in NTSC mode ****
	lea GfxName(PC),a1
	jsr _LVOOldOpenLibrary(a6)				; open graphics.library
	move.l d0,a1
	move.w gb_DisplayFlags(a1),d0
	and.b #%11111011,d0						; clear PAL flag
	or.b  #%00000001,d0						; set NTSC flag
	move.w d0,gb_DisplayFlags(a1)
	move.w #200,gb_NormalDisplayRows(a1)	; WorkBench 200 pixels high
	or.b #LIBF_CHANGED,LIB_FLAGS(a1)
	move.l a1,a2
	jsr _LVOSumLibrary(a6)					; recalculate checksum
	move.l a2,a1
	jsr _LVOCloseLibrary(a6)
	move.b #60,VBlankFrequency(a6)		; change VBLANK
	or.b #LIBF_CHANGED,LIB_FLAGS(a6)
	jsr _LVOSumLibrary(a6)					; recalculate checksum

************************
	move.w #0,$dff1dc							; this one does all the magic
************************

endtag:
	movem.l (sp)+,d0-d7/a0-a6				; back to kickstart
	rts

RomTagPtrs:
	dc.l 0,0										; array of RomTag pointers
GfxName:
	dc.b 'graphics.library',0
PortName:
	dc.b 'BootNTSC.port',0					; port name
TagName:
	dc.b 'NTSC-boot',0						; tag name
	EVEN

myMemList:										; memory list for reset protection
	ds.b LN_SIZE
	dc.w 1
	dc.l NULL
	dc.l BlockLen

Port:												; our port structure
	dc.l NULL
	dc.l NULL
	dc.b NT_MSGPORT
	dc.b 0
	dc.l NULL
	dc.b 0
	dc.b 0
	dc.l NULL
	ds.b 14

RomTag:											; the RomTag to inform kickstart
	dc.w RTC_MATCHWORD						; of what we want
	dc.l NULL
	dc.l NULL
	dc.b RTF_COLDSTART
	dc.b 1
	dc.b 0
	dc.b -10
	dc.l NULL
	dc.l NULL
	dc.l 0

BlockLen equ *-StartBlock					; length of block to be copied

*****************************************************************************

	END