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Old 08 August 2014, 20:46   #27
Toni Wilen
WinUAE developer
Join Date: Aug 2001
Location: Hämeenlinna/Finland
Age: 43
Posts: 20,660
I debugged some more and noticed that 68K code also modifies f60020 bit 0. And sometimes BPPC boot code and ppctest.dms powerup tests succeed, even if I ignore bit 0. It seems to be timing sensitive.

Not very optimal code..

68EB54CE 48e7 000e                MOVEM.L A4-A6,-(A7)
68EB54D2 2a4e                     MOVEA.L A6,A5
68EB54D4 7001                     MOVE.L #$00000001,D0
68EB54D6 b0ad 015c                CMP.L (A5, $015c) == $6803555e,D0
68EB54DA 6610                     BNE.B #$00000010 == $68eb54ec
68EB54DC 287c fff1 0082           MOVEA.L #$fff10082,A4
68EB54E2 4e71                     NOP
68EB54E4 18bc 0040                MOVE.B #$40,(A4)
68EB54E8 4e71                     NOP
68EB54EA 6026                     BT .B #$00000026 == $68eb5512
68EB54EC 7002                     MOVE.L #$00000002,D0
68EB54EE b0ad 015c                CMP.L (A5, $015c) == $6803555e,D0
68EB54F2 6610                     BNE.B #$00000010 == $68eb5504
68EB54F4 287c 00f6 0020           MOVEA.L #$00f60020,A4
68EB54FA 4e71                     NOP
68EB54FC 18bc 0001                MOVE.B #$01,(A4)
68EB5500 4e71                     NOP
68EB5502 600e                     BT .B #$0000000e == $68eb5512
68EB5504 287c 00f6 0020           MOVEA.L #$00f60020,A4
68EB550A 4e71                     NOP
68EB550C 18bc 0001                MOVE.B #$01,(A4)
68EB5510 4e71                     NOP
68EB5512 4cdf 7000                MOVEM.L (A7)+,A4-A6
68EB5516 4e75                     RTS

68EB5518 48e7 000e                MOVEM.L A4-A6,-(A7)
68EB551C 2a4e                     MOVEA.L A6,A5
68EB551E 7001                     MOVE.L #$00000001,D0
68EB5520 b0ad 015c                CMP.L (A5, $015c) == $6803555e,D0
68EB5524 6610                     BNE.B #$00000010 == $68eb5536
68EB5526 287c fff1 0082           MOVEA.L #$fff10082,A4
68EB552C 4e71                     NOP
68EB552E 18bc 00c0                MOVE.B #$c0,(A4)
68EB5532 4e71                     NOP
68EB5534 6026                     BT .B #$00000026 == $68eb555c
68EB5536 7002                     MOVE.L #$00000002,D0
68EB5538 b0ad 015c                CMP.L (A5, $015c) == $6803555e,D0
68EB553C 6610                     BNE.B #$00000010 == $68eb554e
68EB553E 287c 00f6 0020           MOVEA.L #$00f60020,A4
68EB5544 4e71                     NOP
68EB5546 18bc 0081                MOVE.B #$81,(A4)
68EB554A 4e71                     NOP
68EB554C 600e                     BT .B #$0000000e == $68eb555c
68EB554E 287c 00f6 0020           MOVEA.L #$00f60020,A4
68EB5554 4e71                     NOP
68EB5556 18bc 0081                MOVE.B #$81,(A4)
68EB555A 4e71                     NOP
68EB555C 4cdf 7000                MOVEM.L (A7)+,A4-A6
68EB5560 4e75                     RTS
Especially these two functions..:

68EB54B6 48e7 0006                MOVEM.L A5-A6,-(A7)
68EB54BA 2a4e                     MOVEA.L A6,A5
68EB54BC 4cdf 6000                MOVEM.L (A7)+,A5-A6
68EB54C0 4e75                     RTS

68EB54C2 48e7 0006                MOVEM.L A5-A6,-(A7)
68EB54C6 2a4e                     MOVEA.L A6,A5
68EB54C8 4cdf 6000                MOVEM.L (A7)+,A5-A6
68EB54CC 4e75                     RTS
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