>Wongck at 11:42, 13 October 2011

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>Wongck at 15:44, 11 October 2011

2011-10-11T15:44:43Z

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			[[Category: Cheats]]

>Muguk at 12:08, 25 September 2008

2008-09-25T12:08:48Z

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	</pre>		</pre>

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>Muguk at 12:08, 25 September 2008

2008-09-25T12:08:24Z

New page

'''Rob Northern Decrypted2 - Xenon 2'''

<pre>
------------------------------------------------------------------------------
RNC - XENON II last revision 2006/12/27
------------------------------------------------------------------------------
$40088:[]move.l a6,(sp)
$4008A:[]lea.l $40016(pc),a6 ; register
$4008E:[]movem.l d0-d7/a0-a7,(a6)
$40092:[]lea.l $40(a6),a6 ; $40056
$40096:[]move.l (sp)+,-$8(a6)
$4009A:[]move.l $10,d0 ; save Illegal vector
$400A0:[]pea $400ac(pc) ;
$400A4:[]move.l (sp)+,$10 ; new Illegal vector
$400AA:[]illegal
------------------------------------------------------------------------------
$400AC:[]move.l d0,$10 ; restore Illegal vector
$400B2:[]movem.l $8,d0-d7 ;
$400BA:[]movem.l d0-d7,(a6) ; save exception vectors
$400BE:[]lea.l $40144(pc),a0 ;
$400C2:[]move.l a0,$10 ; new Illegal vector (toggle Trace)
$400C8:[]lea.l $40080(pc),a0
$400CC:[]move.l a0,(a0)
$400CE:[]illegal ; Trace ON
------------------------------------------------------------------------------
dummy code
------------------------------------------------------------------------------
$400D0:[]bra $400e0
$400D4:[]bra $400fc
$400D8:[]bra $4013c
$400DC:[]bra $40108
$400E0:[]bra $4010c
$400E4:[]bra $400ec
$400E8:[]bra $40104
$400EC:[]bra $4011c
$400F0:[]bra $40138
$400F4:[]bra $40120
$400F8:[]bra $40110
$400FC:[]bra $40114
$40100:[]bra $401aa ; skip this code
$40104:[]bra $40124
$40108:[]bra $400f8
$4010C:[]bra $40140
$40110:[]bra $400d4
$40114:[]bra $400e8
$40118:[]bra $400f4
$4011C:[]bra $40134
$40120:[]bra $400dc
$40124:[]bra $4012c
$40128:[]bra $400d8
$4012C:[]bra $400e4
$40130:[]bra $40118
$40134:[]bra $400f0
$40138:[]bra $40128
$4013C:[]bra $40100
$40140:[]bra $40130
------------------------------------------------------------------------------
new Illegal vector - Trace ON/OFF
------------------------------------------------------------------------------
$40144:[]movem.l d0/a0/a1,-(sp)
$40148:[]lea.l $4017e(pc),a0
$4014C:[]move.l a0,$24 ; new Trace vector
$40152:[]lea.l $406d0,(pc),a0
$40156:[]move.l a0,$20 ; new Privilege Violation vector
$4015C:[]addi.l #$2,$e(sp) ; next PC after illegal op-code
$40164:[]ori.b #$7,$c(sp) ; Supervisor ON
$4016A:[]bchg #$7,$c(sp) ; Trace ON/OFF
$40170:[]lea.l $40080(pc),a1
$40174:[]beq.s $40190
$40176:[]movea.l (a1),a0 ; previous address
$40178:[]move.l $4(a1),(a0) ; restore previous encrypted long word
$4017C:[]bra.s $401a4
------------------------------------------------------------------------------
new Trace vector - encrypt/decrypt
------------------------------------------------------------------------------
$4017E:[]andi.w #$f8ff,sr
$40182:[]movem.l d0/a0/a1,-(sp)
$40186:[]lea.l $40080(pc),a1 ;
$4018A:[]movea.l (a1),a0 ; previous address
$4018C:[]move.l $4(a1),(a0) ; restore previous encrypted long word
$40190:[]movea.l $e(sp),a0 ; current address
$40194:[]move.l a0,(a1) ; save current address
$40196:[]move.l (a0),$4(a1) ; save current encrypted long word
$4019A:[]move.l -$4(a0),d0 ; get long word for decryption
$4019E:[]not.l d0 ;
$401A0:[]swap d0 ;
$401A2:[]eor.l d0,(a0) ; decrypt current address
$401A4:[]movem.l (sp)+,d0/a0/a1
$401A8:[]rte
------------------------------------------------------------------------------
load new exception vectors
------------------------------------------------------------------------------
$401AA:[]move.l $4,$7c
$401B4:[]lea.l $401d4(pc),a0
$401B8:[]movea.l #$8,a1
$401BE:[]lea.l $40088(pc),a4
$401C2:[]moveq.l #$7,d0
$401C4:[]moveq.l #$0,d1
$401C6:[]move.w (a0)+,d1
$401C8:[]add.l a4,d1
$401CA:[]move.l d1,(a1)+
$401CC:[]dbra d0,$401c4
$401D0:[]bra $401e4
$401D4:[]...
$401E4:[]cmpi.b #$fa,$13d
$401EC:[]bne.s $40200
$401EE:[]move.w #$60fe,$7c
$401F6:[]move.l #$1f,$13c
------------------------------------------------------------------------------
$40200:[]lea.l $404d0(pc),a0 ; sector buffer
$40204:[]bsr $4039c ; FDC Init
$40208:[]moveq.l #$6,d2 ; main loop counter
------------------------------------------------------------------------------
main loop - read sectors and compare counter
------------------------------------------------------------------------------
$4020A:[]moveq.l #$0,d0
$4020C:[]subq.l #$1,d2
$4020E:[]beq.s $4026e ; skip after 6 errors
$40210:[]moveq.l #$1,d0
$40212:[]bsr $40276 ; read sector and count
$40216:[]beq.s $4020a
$40218:[]move.l d0,-(sp) ; save first sector counter
$4021A:[]moveq.l #$6,d0 ; RNC sector
$4021C:[]bsr $40276 ; read sector and count
$40220:[]beq.s $4020a
$40222:[]move.l (sp)+,d1 ; restore first sector counter
$40224:[]sub.l d1,d0
$40226:[]bmi.s $4020a ; skip on error
$40228:[]mulu #$64,d0
$4022C:[]divu d1,d0
$4022E:[]cmp.b #$2,d0
$40232:[]blt.s $4020a ; skip on error
------------------------------------------------------------------------------
magic key calculation
------------------------------------------------------------------------------
$40234:[]moveq.l #$5,d1
$40236:[]moveq.l #$0,d0
$40238:[]cmpi.l #$526f6220,(a0) ;'Rob '
$4023E:[]bne.s $4020a
$40240:[]cmpi.l #$4e6f7274,$4(a0) ;'Nort'
$40248:[]bne.s $4020a
$4024A:[]cmpi.l #$68656e20,$8(a0) ;'hen '
$40252:[]bne.s $4020a
$40254:[]cmpi.l #$436f6d70,$c(a0) ;'Comp'
$4025C:[]bne.s $4020a
$4025E:[]add.l (a0)+,d0
$40260:[]rol.l #$3,d0 ; DE534692
$40262:[]dbra d1,$4025e
$40266:[]lea.l $40056(pc),a0
$4026A:[]move.l d0,$1c(a0) ; <<< save magic key for xor ($406DC)
$4026E:[]bsr $403d4 ; clean up
$40272:[]bra $404a2 ; exit
------------------------------------------------------------------------------
read sector in d0 and return counter
------------------------------------------------------------------------------
$40276:[]movem.l d1-d3/a1,-(sp)
$4027A:[]bsr $4028c
$4027E:[]tst.w d0
$40280:[]beq.s $40284
$40282:[]moveq.l #$0,d1
$40284:[]move.l d1,d0
$40286:[]movem.l (sp+),d1-d3/a1
$4028A:[]rts
------------------------------------------------------------------------------
DMA read
------------------------------------------------------------------------------
$4028C:[]move.w #$84,$ff8606
$40294:[]move.w d0,$ff8604
$4029A:[]move.l a0,d0 ; sector buffer $404d0
$4029C:[]move.b d0,$ff860d ; DMA low
$402A2:[]lsr.l #$8,d0 ;
$402A4:[]move.b d0,$ff860b ; DMA mid
$402AA:[]lsr.l #$8,d0 ;
$402AC:[]move.b d0,$ff8609 ; DMA high
$402B2:[]move.w #$90,$ff8606 ;
$402BA:[]move.w #$190,$ff8606 ; toggle DMA read
$402C2:[]move.w #$90,$ff8606 ;
$402CA:[]move.w #$16,$ff8604 ; 512 byte blocks
$402D2:[]move.w #$80,$ff8606 ; select command register
$402DA:[]lea.l $ff860b,a1
$402E0:[]moveq.l #$0,d1 ; clear counter
$402E2:[]move.l a0,d2
$402E4:[]move.l #$61a80,d3
$402EA:[]illegal ; Trace OFF (timing)
$402EC:[]move.w #$80,$ff8604 ; read sector
$402F4:[]subq.l #$1,d3
$402F6:[]beq.s $4032a
$402F8:[]movep.w $0(a1),d0
$402FC:[]cmp.w d0,d2
$402FE:[]beq.s $402f4
$40300:[]addi.l #$200,d2
$40306:[]addq.l #$1,d1 ; counter+1
$40308:[]movep.w $0(a1),d0
$4030C:[]cmp.w d0,d2
$4030E:[]bne.s $40306
$40310:[]subq.l #$1,d3
$40312:[]beq.s $4032a ; Force Interrupt (skip on error)
$40314:[]btst #$5,$fffa01 ; ready?
$4031C:[]bne.s $40310
$4031E:[]illegal ; Trace ON
$40320:[]bsr $40486 ; get status
$40324:[]andi.w #$10,d0
$40328:[]rts
------------------------------------------------------------------------------
Force Interrupt (skip on error)
------------------------------------------------------------------------------
$4032A:[]bsr $4046e
$4032E:[]moveq.l #$ffffffff,d0
$40330:[]rts
------------------------------------------------------------------------------
FDC Seek in d2
------------------------------------------------------------------------------
$40332:[]move.w #$86,$ff8606
$4033A:[]move.w d2,$ff8604
$40340:[]move.w #$14,d0 ; seek
$40344:[]bsr $40440 ; FDC command in d0
$40348:[]bmi.s $4035a ; skip on error
$4034A:[]move.w $40076(pc),d0
$4034E:[]lsl.w #$1,d0
$40350:[]lea.l $40078(pc),a0
$40354:[]move.w d2,$0(a0,d0.w)
$40358:[]moveq.l #$0,d0
$4035A:[]rts
------------------------------------------------------------------------------
skip on error
------------------------------------------------------------------------------
$4035C:[]moveq.l #$54,d1
$4035E:[]bsr $4046e ; Force Interrupt
$40362:[]btst #$2,d0 ; Track 00?
$40366:[]bne.s $40378
$40368:[]moveq.l #$60,d0 ; step-out
$4036A:[]bsr $40440 ; FDC command in d0
$4036E:[]bmi.s $40374
$40370:[]subq.l #$1,d1
$40372:[]bne.s $40362
$40374:[]moveq.l #$ffffffff,d0
$40376:[]rts
$40378:[]moveq.l #$54,d2
$4037A:[]sub.l d1,d2
$4037C:[]move.w $40076(pc),d0
$40380:[]lsl.l #$1,d0
$40382:[]lea.l $40078(pc),a0
$40386:[]clr.w $0(a0,d0.w)
$4038A:[]move.w #$82,$ff8606 ; Track register
$40392:[]moveq.l #$0,d0 ;
$40394:[]move.w d0,$ff8604 ;
$4039A:[]rts
------------------------------------------------------------------------------
FDC Init
------------------------------------------------------------------------------
$4039C:[]movem.l d0-d2/a0,-(sp)
$403A0:[]lea.l $4007e(pc),a0
$403A4:[]move.w $43e,(a0) ; save Flock
$403AA:[]st $43e ; set
$403B0:[]move.w #$82,$ff8606 ; Track register
$403B8:[]move.w $ff8604,d2
$403BE:[]lea.l $4007c(pc),a0
$403C2:[]move.w d2,(a0) ; save Track Register
$403C4:[]bsr $403f2 ; Drive select
$403C8:[]moveq.l #$0,d0 ; Restore
$403CA:[]bsr $40440 ; FDC command in d0
$403CE:[]movem.l (sp)+,d0-d2/a0
$403D2:[]rts
------------------------------------------------------------------------------
FDC end
------------------------------------------------------------------------------
$403D4:[]movem.l d0-d2/a0,-(sp)
$403D8:[]move.w $4007c(pc),d2 ; Track
$403DC:[]bsr $40332 ; FDC Seek
$403E0:[]bsr $40426 ; Drive deselect
$403E4:[]move.w $4007e(pc),$43e ; restore Flock
$403EC:[]movem.l (sp)+,d0-d2/a0
$403F0:[]rts
------------------------------------------------------------------------------
Drive select
------------------------------------------------------------------------------
$403F2:[]move.w $40076(pc),d0
$403F6:[]addq.b #$1,d0
$403F8:[]lsl.b #$1,d0
$403FA:[]ori.w #$0,d0
$403FE:[]eori.b #$7,d0
$40402:[]andi.b #$7,d0
$40406:[]illegal ; Trace OFF
$40408:[]move.b #$e,$ff8800
$40410:[]move.b $ff8800,d1
$40416:[]andi.b #$f8,d1
$4041A:[]or.b d0,d1
$4041C:[]move.b d1,$ff8802
$40422:[]illegal ; Trace ON
$40424:[]rts
------------------------------------------------------------------------------
Drive deselect
------------------------------------------------------------------------------
$40426:[]movem.l d0/d1,-(sp)
$4042A:[]move.w #$3a98,d0
$4042E:[]bsr $4049c ; wait
$40432:[]move.b #$7,d0
$40436:[]bsr $40406
$4043A:[]movem.l (sp)+,d0/d1
$4043E:[]rts
------------------------------------------------------------------------------
FDC command in d0
------------------------------------------------------------------------------
$40440:[]ori.w #$3,d0
$40444:[]move.w #$80,$ff8606
$4044C:[]move.w d0,$ff8604
$40452:[]move.l #$60000,d0
$40458:[]btst #$5,$fffa01 ; ready?
$40460:[]beq.s $40486 ; get status
$40462:[]subq.l #$1,d0
$40464:[]bne.s $40458
$40466:[]bsr $4046e ; Force Interrupt
$4046A:[]moveq.l #$ffffffff,d0
$4046C:[]rts
------------------------------------------------------------------------------
DMA Force Interrupt
------------------------------------------------------------------------------
$4046E:[]move.w #$80,$ff8606
$40476:[]move.w #$d0,$ff8604
$4047E:[]move.w #$f,d0
$40482:[]bsr $4049c ; wait
$40486:[]move.w #$80,$ff8606
$4048E:[]moveq.l #$0,d0
$40490:[]move.w $ff8604,d0 ; get status
$40496:[]andi.w #$1f,d0
$4049A:[]rts
------------------------------------------------------------------------------
wait d0
------------------------------------------------------------------------------
$4049C:[]dbra d0,$4049c
$404A0:[]rts
------------------------------------------------------------------------------
exit
------------------------------------------------------------------------------
$404A2:[]lea.l $40016(pc),a0
$404A6:[]move.l d0,(a0) ; magic key
$404A8:[]movem.l $40056(pc),d0-d7 ; old exception vectors magic key = d7
$404AE:[]move.l $4,d0
$404B4:[]move.l d0,d1
$404B6:[]lea.l $406d0(pc),a0 ; <<< next PC
$404BA:[]move.l a0,$2(sp)
$404BE:[]illegal ; Trace OFF
$404C0:[]movem.l d0-d7,$8 ; restore exception vectors
$404C8:[]movem.l $40016(pc),d0-d7/a0-a6 ; magic key in d0
$404CE:[]rte
------------------------------------------------------------------------------
$404D0: 52 6F 62 20 4E 6F 72 74 68 65 6E 20 43 6F 6D 70 Rob Northen Comp
$404E0: 6C C6 06 66 A6 AB 2A DF C9 E4 13 C8 27 90 4F 20 l..f..*.......O
------------------------------------------------------------------------------
</pre>

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Rob Northern Decrypted2 - Revision history

>Wongck at 11:42, 13 October 2011

>Wongck at 15:44, 11 October 2011

>Muguk at 12:08, 25 September 2008

>Muguk at 12:08, 25 September 2008