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apple2_fantavision_reloaded
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More cleanup P5 Boot vars

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Michaelangel007 2017-03-26 13:01:19 -07:00
parent 5c4df0a80c
commit 87e8106abe
1 changed files with 13 additions and 4 deletions
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@ -528,7 +528,16 @@ On my //e it looks this:
P5.Dest = $26 ; 16-bit pointer to dest
P5.SlotX16 = $2B ; i.e. $60 = Slot 6
; Magic Numbers "disk nisk nibbles"
P5.Nibs = $3C ; counter for $56 nibbles
P5.SecHave = $3C ; last rest Vol, Track, Sec stored here
P5.SecWant = $3D ;
P5.SecTotal = $0800 ; T00S0 @ $00: total number of sectors to load
P5.TrackHave = $40
P5.TrackWant = $41 ;
; Magic Numbers "disk nibbles"
ADDR_PROLOG_1 = $D5
ADDR_PROLOG_2 = $AA
ADDR_PROLOG_3 = $96
@ -568,18 +577,18 @@ On my //e it looks this:
C687:BD 8C C0 ^8 LDA DRIVE_DATA,X
C68A:10 FB BPL ^8 ;^ $C687 mask = $FF since: C=1 from $C676
C68C:2A ROL ; ... 4&4 encoded: 1a1c1e1g, C=1 since A > $80
C68D:85 3C STA $3C ; ... 1st half A= a1c1e1gC
C68D:85 3C STA P5.SecHave ; ... 1st half A= a1c1e1gC
C68F:BD 8C C0 ^9 LDA DRIVE_DATA,X
C692:10 FB BPL ^9 ;^ $C68F &= 1b1d1f1h
C694:25 3C AND $3C ; ... 2nd half = abcdefgh
C694:25 3C AND P5.SecHave ; ... 2nd half = abcdefgh
C696:88 DEY
C697:D0 EC BNE ^7 ;^ $C685
C699:28 PLP ; Don't care about carry, restore stack
C69A:C5 3D CMP P5.SecWant ; A=SectorHave == SectorWant? (init $00 from $C654)
C69C:D0 BE BNE ^0 ;^ $C65C
C69E:A5 40 LDA P5.TrackHave ; (read from prologue)
C6A0:C5 41 CMP TrackWant ;
C6A0:C5 41 CMP P5.TrackWant
C6A2:D0 B8 BNE ^0 ;^ $C65C !=
C6A4:B0 B7 BCS ^1 ;^ $C65D >=
C6A6:A0 56 ^10 LDY #$56 ; Decode $56 nibbles in 6&2