4cade/src/proboothd/proboothd.a
2021-08-13 20:53:38 -04:00

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;license:BSD-3-Clause
;minimal open/read binary file in ProDOS filesystem
;copyright (c) Peter Ferrie 2016-2019
!cpu 6502
!to "build/proboothd",plain
*=$800
;zpage usage, arbitrary selection except for the "ProDOS constant" ones
command = $42 ;ProDOS constant
unit = $43 ;ProDOS constant
adrlo = $44 ;ProDOS constant
adrhi = $45 ;ProDOS constant
bloklo = $46 ;ProDOS constant
blokhi = $47 ;ProDOS constant
A2L = $3e
A2H = $3f
sizehi = $53
;constants
scrn2p2 = $f87b
dirbuf = $1e00 ;for size-optimisation
!byte 1
txa
pha
; put machine in a known state, clear screen
cld
bit $c082
sta $c00e
sta $c00c
sta $c000
sta $c002
sta $c004
lda $c000
cmp #$d3
bne +
jsr seasons
+ jsr $fb2f
jsr $fc58
jsr $fe84
jsr $fe89
jsr $fe93
; print title
ldy #11
- lda TOTAL-1, y
sta $04B6-1, y
lda REPLAY-1, y
sta $0536-1, y
dey
bne -
pla
sta unit
tax
; X = boot slot x16
; Y = 0
; set up ProDOS shim
- txa
jsr scrn2p2
and #7
ora #$c0
sta $be30, y
sta slot+2
sta entry+2
slot lda $cfff
sta entry+1
lda fakeMLI_e-$100, y
sta $be00+fakeMLI_e-fakeMLI, y
iny
bne -
sty adrlo
stx $bf30
sty $200
opendir ;read volume directory key block
ldx #2
;include volume directory header in count
firstent lda #>dirbuf
sta adrhi
sta A2H
jsr seekread
lda #4
sta A2L
nextent ldy #0
;match name lengths before attempting to match names
lda (A2L), y
and #$0f
tax
inx
- cmp filename, y
beq foundname
;move to next directory in this block
clc
lda A2L
adc #$27
sta A2L
bcc +
;there can be only one page crossed, so we can increment instead of adc
inc A2H
+ cmp #$ff ;4+($27*$0d)
bne nextent
;read next directory block when we reach the end of this block
ldx dirbuf+2
ldy dirbuf+3
bcs firstent
foundname
iny
lda (A2L), y
dex
bne -
stx $ff
;cache KEY_POINTER
ldy #$11
lda (A2L), y
tax
iny
lda (A2L), y
tay
readfile jsr seekread
inc adrhi
inc adrhi
;fetch data block and read it
blockind ldy $ff
inc $ff
ldx dirbuf, y
lda dirbuf+256, y
tay
bne readfile
txa
bne readfile
readdone jmp $203b
seekread stx bloklo
sty blokhi
lda #1
sta command
lda adrhi
pha
entry jsr $d1d1
pla
sta adrhi
rts
fakeMLI bne retcall
readblk dey
dey
sty adrhi
tay
jsr $bf00+seekread-fakeMLI
retcall pla
tax
inx
inx
inx
txa
pha
- rts
fakeMLI_e
; Interactive Seasons demo
; based on Apple II Seasons -=DESiRE=- 128B Demo for Outline 2020
; based on the code in Hellmood's 64B x86 demo 'Autumn'
; by deater (Vince Weaver)
; adapted by 4am for use within this bootloader
; /!\ While demo is running, press 1-4 to change color palettes
; or Esc to quit demo and continue the boot
HGR2 = $F3D8 ; Set full-screen hi-res mode using page 2 ($4000)
HPLOT0 = $F457 ; Plot point, (Y,X) = Horizontal, (A=Vertical)
HCOLOR = $F6EC ; Set color in X, must be 0..7
seasons:
bit $c010
jsr HGR2
ldx #(copy_seasons_e-copy_seasons)
- lda copy_seasons-1, x
sta $30, x
dex
bne -
jmp seasons_forever
copy_seasons:
; HGR ROM routines use
; $1C mask for color
; $26/$27 address for plot
; $30 color value * 17
; $E0/$E1 X coord of last hplot
; so code starts at $31 and must end before $E0
!pseudopc $31 {
EBP1 !byte 0
EBP2 !byte 0
EBP3 !byte 0
EBP4 !byte 0
color_lookup_lookup:
!byte <color_lookup
!byte <color_lookup2
!byte <color_lookup3
!byte <color_lookup4
color_lookup:
; qkumba ora2 white/blue/purple
!byte $02,$03,$02,$03, $06,$07,$06,$07
color_lookup2:
; better mixed orange/green/white
!byte $01,$03,$03,$03, $05,$05,$07,$07
color_lookup3:
; blue and purple palette
!byte $02,$02,$03,$06, $06,$06,$02,$07
color_lookup4:
; colorful palette
!byte $01,$01,$02,$03, $05,$05,$06,$07
seasons_forever:
; save old Xcoord value to X/Y for later
XCOORDL=*+1
ldx #0 ; 2
XCOORDH=*+1
ldy #0 ; 2
; 16-bit subtraction x=x-y
; need to set carry before subtraction on 6502
txa ; 1 (xcoordl in X)
sec ; 1
sbc <YCOORDL ; 2
sta <XCOORDL ; 2
tya ; 1 (xcoordh in Y)
YCOORDH=*+1
sbc #0 ; 2
; 16-bit arithmetic shift right of X
; 6502 has no asr instruction
; cmp #$80 sets carry if high bit set
cmp #$80 ; 2 ; XCOORDH still in A from before
ror ; 1
sta <XCOORDH ; 2
ror <XCOORDL ; 2
; 16-bit add, ycoord=ycoord+oldx
clc ; 1
txa ; 1
YCOORDL=*+1
adc #0 ; 2
sta <YCOORDL ; 2
tya ; 1
adc <YCOORDH ; 2
; 16-bit arithmetic shift right of y-coord
cmp #$80 ; 2 ; YCOORDH still in A from before
ror ; 1
sta <YCOORDH ; 2
ror <YCOORDL ; 2
; 32 bit rotate of low bit shifted out of Y-coordinate
ror <EBP1 ; 2
ror <EBP2 ; 2
ror <EBP3 ; 2
ror <EBP4 ; 2
; branch if carry set
bcs label_11f ; 2
; 16-bit increment of color
inc <COLORL ; 2
bne no_oflo ; 2
inc <COLORH ; 2
no_oflo:
; 16-bit add of X-coord by 0x80
; this keeps the drawing roughly to the 280x192 screen
; carry should still be clear (inc doesn't set it)
lda <XCOORDL ; 2
adc #$80 ; 2
sta <XCOORDL ; 2
bcc no_oflo2 ; 2
inc <XCOORDH ; 2
no_oflo2:
; 16-bit negate of Y-coord
sec ; 1
lda #0 ; 2
sbc <YCOORDL ; 2
sta <YCOORDL ; 2
lda #0 ; 2
sbc <YCOORDH ; 2
sta <YCOORDH ; 2
label_11f:
; 16-bit shift of color
; 2nd is a rotate as asl doesn't shift in carry
COLORL=*+1
lda #0 ; 2
asl ; 1 ; shl %ax
rol <COLORH ; 2
COLORH=*+1
eor #0 ; 2
sta <COLORL ; 2
; get color mapping
and #7 ; 2
tay ; 1
color_addr=*+1
ldx <color_lookup, y ; 2
; if ycoord negative, loop
lda <YCOORDH ; 2
bmi seasons_forever ; 2
; if top bits of xcoord, loop
lda <XCOORDH ; 2
and #$f0 ; 2
bne seasons_forever ; 2
put_pixel:
; actually set the color
jsr HCOLOR ; 3 ; color is in X
; set up parameters for HPLOT ROM call
ldx <XCOORDL ; 2 ; x coord in (y:x)
ldy <XCOORDH ; 2
lda <YCOORDL ; 2 ; y coord in A
jsr HPLOT0 ; 3
lda $c000
- bpl seasons_forever
cmp #$9b
beq +
and #3
tax
lda <color_lookup_lookup, x
sta <color_addr
bpl - ; always branches
+ rts
}
copy_seasons_e
filename
!byte filename_e - filename_b
filename_b
!text "LAUNCHER.SYSTEM" ;your start-up file, file is max 40kb
filename_e
TOTAL
!byte $A0,$D4,$A0,$CF,$A0,$D4,$A0,$C1,$A0,$CC,$A0
REPLAY
!byte $D2,$A0,$C5,$A0,$D0,$A0,$CC,$A0,$C1,$A0,$D9
*=$9f8
!byte $D3,$C1,$CE,$A0,$C9,$CE,$C3,$AE