2413 lines
60 KiB
ArmAsm
2413 lines
60 KiB
ArmAsm
;==============================================================
|
|
;SOS GRAPHICS DRIVER
|
|
;(C) Apple Computer, Inc., 1983 v1.3
|
|
; - edited 3/24/86 to 8/31/86 by Erik Olbrys CIS 71236,1245
|
|
;==============================================================
|
|
|
|
.feature labels_without_colons
|
|
.setcpu "6502"
|
|
.reloc
|
|
;
|
|
;driver comment field
|
|
;this is put in the TEXT segment so we can get the lenght and output it ok
|
|
;
|
|
.segment "TEXT"
|
|
.word $FFFF ;Comment follows..
|
|
.word $0039 ;$39 bytes long
|
|
.byte "Copyright (C) 1983 Apple Computer, Inc. Graphics Driver."
|
|
|
|
;
|
|
;Driver code part
|
|
;this is put in the DATA segement
|
|
;
|
|
|
|
.segment "DATA"
|
|
|
|
DEVTYPE = $62 ;Character device, read/write
|
|
SUBTYPE = $01 ;Device subtype
|
|
MANID = $01 ;Manufacturer ID - Apple Inc.
|
|
RELEASE = $1300 ;Release number in BCD format
|
|
|
|
;-------------------
|
|
;N-WAY SWITCH MACRO
|
|
;SWITCH [index], [bounds], adrs_table, [*]
|
|
;-------------------
|
|
|
|
.MACRO SWITCH index,bounds,adrs_table ;,noexec ;See SOS Reference
|
|
.IFNBLANK index ;If PARM1 is present,
|
|
LDA index ; load A with switch index
|
|
.ENDIF
|
|
.IFNBLANK bounds ;If PARM2 is present,
|
|
CMP #bounds+1 ; perform bounds checking
|
|
BCS @110 ; on switch index
|
|
.ENDIF
|
|
ASL A ;Multiply by 2 for table index
|
|
TAY
|
|
LDA adrs_table+1,Y ;Get switch address from table
|
|
PHA ; and push onto Stack
|
|
LDA adrs_table,Y
|
|
PHA
|
|
; .IF noexec <> "*" ;If PARM4 is omitted,
|
|
RTS ; exit to code
|
|
; .ENDIF
|
|
@110 .ENDMACRO
|
|
|
|
;--------------------
|
|
;INCREMENT WORD MACRO
|
|
;--------------------
|
|
|
|
.MACRO INW inword
|
|
INC inword ;Increment low-order
|
|
BNE @210 ;If 'Carry',
|
|
INC inword+1 ; increment high-order
|
|
@210 .ENDMACRO
|
|
|
|
;------------------------------
|
|
;INCREMENT 3-BYTE ADDRESS MACRO
|
|
;------------------------------
|
|
|
|
.MACRO INCADR addr
|
|
INC addr
|
|
BNE @310
|
|
INC addr+1
|
|
BNE @310 ;Bank overflow?
|
|
LDX #$80 ;Yes
|
|
STX addr+1
|
|
INC addr+1+$1400 ;Increment X-byte
|
|
@310 .ENDMACRO
|
|
|
|
.PROC GRAFIX
|
|
|
|
;---------------
|
|
;GENERAL EQUATES
|
|
;---------------
|
|
|
|
TRUE = $80
|
|
FALSE = $00
|
|
BITON0 = $01
|
|
BITON1 = $02
|
|
BITON2 = $04
|
|
BITON3 = $08
|
|
BITON4 = $10
|
|
BITON5 = $20
|
|
BITON6 = $40
|
|
BITON7 = $80
|
|
|
|
;-----------------------------
|
|
;SOS GLOBAL DATA & SUBROUTINES
|
|
;-----------------------------
|
|
|
|
SCR_MODE = $1906
|
|
MEM_FLAG = $1907 ;amount of mem reserved for grafix
|
|
SYSERR = $1928 ;report error to system
|
|
|
|
;----------------------------
|
|
;SOS DEVICE HANDLER INTERFACE
|
|
;----------------------------
|
|
|
|
SOSINT = $C0
|
|
REQCODE = SOSINT+0 ;SOS request code
|
|
BUFFER = SOSINT+2 ;Buffer pointer
|
|
REQCNT = SOSINT+4 ;Requested count/byte count
|
|
CTLSTAT = SOSINT+2 ;Control/status code
|
|
CSLIST = SOSINT+3 ;Control/status list pointer
|
|
RETPTR = SOSINT+8 ;Returned count pointer
|
|
|
|
;--------------------
|
|
;HARDWARE I/O ADDRESS
|
|
;--------------------
|
|
|
|
SETBW = $C050 ;black & white on
|
|
SETCOL = $C051 ;color on
|
|
COLM40 = $C052 ;set 40 columns
|
|
COLM80 = $C053 ;set 80 columns
|
|
LOWSCR = $C054 ;set page one
|
|
HISCR = $C055 ;set page two
|
|
TEXT = $C056 ;set text mode
|
|
HIRES = $C057 ;set hires grafix mode
|
|
|
|
;---------------
|
|
;SOS ERROR CODES
|
|
;---------------
|
|
|
|
XREQCODE = $20 ;invalid request code
|
|
XCTLCODE = $21 ;invalid control/status code
|
|
XCTLPARAM = $22 ;invalid control/status param
|
|
XNOTOPEN = $23 ;device not open
|
|
XNOTAVAIL = $24 ;device not available
|
|
XNORESRC = $25 ;resource not available
|
|
XBADOP = $26 ;invalid operation
|
|
XBADMEM = $30 ;insufficient amount of memory alocated
|
|
|
|
;-----------------
|
|
;ZERO PAGE EQUATES
|
|
;-----------------
|
|
|
|
ZPC9 = $C9
|
|
ZPCA = $CA
|
|
ZPCB = $CB
|
|
ZPCC = $CC
|
|
ZPCD = $CD
|
|
ZPCE = $CE
|
|
ZPCF = $CF
|
|
ZPD0 = $D0
|
|
ZPD1 = $D1
|
|
ZPD2 = $D2
|
|
ZPD3 = $D3
|
|
ZPD4 = $D4
|
|
ZPD5 = $D5
|
|
ZPD6 = $D6
|
|
ZPD7 = $D7
|
|
ZPD8 = $D8
|
|
ZPD9 = $D9
|
|
ZPDA = $DA
|
|
ZPDB = $DB
|
|
ZPDC = $DC
|
|
ZPDD = $DD
|
|
ZPDE = $DE
|
|
ZPDF = $DF
|
|
ZPE0 = $E0
|
|
ZPE1 = $E1
|
|
ZPE2 = $E2
|
|
ZPE3 = $E3
|
|
ZPE4 = $E4
|
|
ZPE5 = $E5
|
|
ZPE6 = $E6
|
|
ZPE7 = $E7
|
|
ZPE8 = $E8
|
|
ZPE9 = $E9
|
|
ZPEA = $EA
|
|
ZPEB = $EB
|
|
ZPEC = $EC
|
|
ZPED = $ED
|
|
ZPEE = $EE
|
|
ZPEF = $EF
|
|
ZPF0 = $F0
|
|
ZPF1 = $F1
|
|
ZPF2 = $F2
|
|
ZPF3 = $F3
|
|
ZPF4 = $F4
|
|
ZPF5 = $F5
|
|
ZPF6 = $F6
|
|
ZPF7 = $F7
|
|
ZPF8 = $F8
|
|
ZPF9 = $F9
|
|
ZPFA = $FA
|
|
ZPFB = $FB
|
|
ZPFC = $FC
|
|
ZPFD = $FD
|
|
ZPFE = $FE
|
|
ZPFF = $FF
|
|
|
|
|
|
; ---------------------------
|
|
; Device Identification res
|
|
; ---------------------------
|
|
|
|
DIB .word 0000 ; link
|
|
.word START ; entry point
|
|
.byte 07 ; name len
|
|
.byte ".GRAFIX " ; device name
|
|
.byte TRUE ; status -- active
|
|
.byte FALSE ; slot -- N/A
|
|
.byte 00 ; unit #
|
|
.byte DEVTYPE ; type
|
|
.byte SUBTYPE ; subtype
|
|
.byte 00 ; reserved for future use
|
|
.word 0000 ; # res s -- none
|
|
.word MANID ; man id -- Apple Inc.
|
|
.word RELEASE ; ver # -- 1.30
|
|
|
|
CNFBLK .word $0096 ; DCB length
|
|
DCB .byte $00 ;graphics mode
|
|
.byte $00 ;transfer mode
|
|
.word $0000 ;cursor x-position
|
|
.word $0000 ; y-position
|
|
.word $0000 ;viewport left edge
|
|
.word $0117 ; right edge:= 279.
|
|
.word $0000 ; bottom edge
|
|
.word $00BF ; top edge:= 191.
|
|
.byte $0F ;pencolor:= white
|
|
.byte $00 ;fillcolor:= black
|
|
.word $0C00 ;Character font address
|
|
.byte $00 ; address X-Byte
|
|
.byte $07 ;character cell bit width
|
|
.byte $08 ;character cell bit height
|
|
.byte $80 ; "Not currently used" (but it IS used)
|
|
|
|
COLT2 .res 8,$00 ; Color operator table
|
|
.res 8,$11
|
|
.res 8,$22
|
|
.res 8,$33
|
|
.res 8,$44
|
|
.res 8,$55
|
|
.res 8,$66
|
|
.res 8,$77
|
|
.res 8,$88
|
|
.res 8,$99
|
|
.res 8,$AA
|
|
.res 8,$BB
|
|
.res 8,$CC
|
|
.res 8,$DD
|
|
.res 8,$EE
|
|
.res 8,$FF
|
|
|
|
DCB_LN = *-DCB
|
|
|
|
L00F5 .res $0E,$00 ;some storage space
|
|
|
|
; duplicate DCB -- used when restoring configuration
|
|
|
|
CNTL_PARAM .byte $00
|
|
GMODE .byte $00 ;graphics mode
|
|
XFMODE .byte $00 ;transfer mode
|
|
XPOS .word $0000 ;cursor x-position
|
|
YPOS .word $0000 ; y-position
|
|
VPORT_L .word $0000 ;viewport left edge
|
|
VPORT_R .word $0117 ; right edge = 279.
|
|
VPORT_B .word $0000 ; bottom edge
|
|
VPORT_T .word $00BF ; top edge = 191.
|
|
PN_COL .byte $0F ;pencolor = white
|
|
F_COL .byte $00 ;fillcolor = black
|
|
FONT .word $0C00 ;Character font address
|
|
FONT_XB .byte $00 ; address X-Byte
|
|
FWIDTH .byte $07 ;character cell bit width
|
|
FHEIGHT .byte $08 ;character cell bit height
|
|
NOT_USED .byte $80 ; "Not currently used"
|
|
|
|
COL_TAB .res 8,$00 ; Color operator table
|
|
.res 8,$11
|
|
.res 8,$22
|
|
.res 8,$33
|
|
.res 8,$44
|
|
.res 8,$55
|
|
.res 8,$66
|
|
.res 8,$77
|
|
.res 8,$88
|
|
.res 8,$99
|
|
.res 8,$AA
|
|
.res 8,$BB
|
|
.res 8,$CC
|
|
.res 8,$DD
|
|
.res 8,$EE
|
|
.res 8,$FF
|
|
|
|
.byte "(C) 1980 Apple Computer"
|
|
|
|
OPENFLG .byte 00 ;open/close flag
|
|
L01B2 .byte 00 ;base addr-hi temp
|
|
L01B3 .byte 00 ;alt base addr-hi temp
|
|
BYT_OFF .word 0008 ;byte offset of a font character
|
|
L01B6 .byte 00 ; \
|
|
L01B7 .byte 00 ; bit pattern used
|
|
L01B8 .byte 00 ; in CLRVIEW
|
|
L01B9 .byte 00 ; /
|
|
|
|
CHR_TEMP .byte 00
|
|
CHR_INDX .byte 00 ;input buffer byte count
|
|
CHR_BUFF .res $20, 00 ;input buffer - copied from the D_WRITE buffer
|
|
|
|
WIDTH_B .byte 01 ;byte width of font character
|
|
|
|
L01DD .byte 00, 00, 00, 00, 00, 07, 00, 08, 00
|
|
L01E6 .byte 00, 00
|
|
L01E8 .byte 00
|
|
|
|
MVR_LO .byte $17, $17, $2F, $8B ;max viewport right, low byte (indexed)
|
|
MVT_LO .byte $BF ;max viewport top, low byte
|
|
MVR_HI .byte $01, $01, $02, $00 ;max viewport right, high byte
|
|
MVT_HI .byte $00 ;max viewport top, high byte
|
|
|
|
L01F3 .byte 00, 00, 01, 01, 02, 02, 03, 03, 00, 00, 01
|
|
L01FE .byte 01, 02, 02, 03, 03, 00, 00, 01, 01, 02, 02, 03, 03
|
|
|
|
L020B .byte $00,$80,$00,$80,$00,$80,$00,$80 ;base addr lo-byte, by y coord
|
|
.byte $28,$A8,$28,$A8,$28,$A8,$28,$A8
|
|
.byte $50,$D0,$50,$D0,$50,$D0,$50,$D0
|
|
|
|
L0223 .byte $20,$20,$20,$20,$40,$60,$60,$60 ;base addr hi-byte, by GMODE
|
|
|
|
;required-memory bits for gmodes 0..7 -- must be =< val in $1907 (MEM_FLAG)
|
|
; also doubles as alternate base-address_hi
|
|
REQD_MEM .byte $20,$40,$40,$40,$40,$80,$80,$80
|
|
|
|
L0233 .byte $00,$01,$1E,$60,$00,$07,$78
|
|
L023A .byte $0F,$70,$00,$03,$3C,$40,$00,$0F,$0F
|
|
.byte $0F,$0F,$0F,$0F,$0F
|
|
.byte $01,$02,$04,$08,$10,$20,$40,$80
|
|
L0250 .byte $15,$0E,$07,$00
|
|
L0254 .byte $0E,$0E,$1C,$07
|
|
L0258 .byte $03
|
|
L0259 .byte $04
|
|
L025A .byte $1C
|
|
|
|
START SWITCH REQCODE, 8, REQSW
|
|
|
|
BADREQ LDA #XREQCODE ;switch fell through -
|
|
JSR SYSERR ; Invalids request code error
|
|
|
|
NOTOPEN LDA #XNOTOPEN ;Graphics driver not open error
|
|
JSR SYSERR
|
|
|
|
REQSW = * ; dispatch table
|
|
.word D_READ-1
|
|
.word D_WRITE-1
|
|
.word D_STATUS-1
|
|
.word D_CONTRL-1
|
|
.word BADREQ-1 ;not implemented
|
|
.word BADREQ-1 ;not implemented
|
|
.word D_OPEN-1
|
|
.word D_CLOSE-1
|
|
.word D_INIT-1
|
|
|
|
|
|
D_INIT LDA #FALSE
|
|
STA OPENFLG ;set it as closed
|
|
RTS
|
|
|
|
|
|
D_OPEN BIT OPENFLG ;is it already open?
|
|
BPL @1
|
|
LDA #XNOTAVAIL ;yep -- it's not available,
|
|
JSR SYSERR ; complain, never returns
|
|
|
|
@1 JSR CONT0 ;initilize device
|
|
LDA #TRUE ;set it as open
|
|
STA OPENFLG
|
|
RTS
|
|
|
|
|
|
D_CLOSE ASL OPENFLG ;close it
|
|
BCS @1
|
|
JMP NOTOPEN ;but it's not open! complain
|
|
@1 RTS
|
|
|
|
|
|
D_STATUS BIT OPENFLG ;is it open?
|
|
BMI @1
|
|
JMP NOTOPEN
|
|
@1 SWITCH CTLSTAT, 2, STATSW
|
|
|
|
DST_ERR LDA #XCTLCODE ;invalid status code
|
|
JSR SYSERR
|
|
|
|
STATSW .word STAT0-1 ;NOP
|
|
.word STAT1-1 ;preserve status table
|
|
.word STAT2-1 ;unknown
|
|
|
|
STAT0 RTS ;nop
|
|
|
|
STAT1 LDY #$00 ;preserve status table
|
|
LDA (CSLIST),Y
|
|
CMP #DCB_LN
|
|
BCS @3
|
|
LDA #XCTLPARAM
|
|
JSR SYSERR
|
|
@3 LDA #DCB_LN
|
|
STA (CSLIST),Y
|
|
TAY
|
|
@4 LDA CNTL_PARAM,Y
|
|
STA (CSLIST),Y
|
|
DEY
|
|
BNE @4
|
|
RTS
|
|
|
|
STAT2 LDY #$00 ;Return newline status
|
|
LDA #$00 ; always =0, only satisfying the proper
|
|
STA (CSLIST),Y ; character count will terminate an input,
|
|
RTS ; as opposed to terminating at newline char
|
|
|
|
|
|
D_CONTRL BIT OPENFLG ;is it open?
|
|
BMI @1
|
|
JMP NOTOPEN
|
|
@1 SWITCH CTLSTAT, 2, CNTLSW
|
|
|
|
@2 JMP DST_ERR
|
|
|
|
CNTLSW .word CONT0-1 ;Device reset
|
|
.word CONT1-1 ;Restore status table
|
|
.word CONT2-1 ;NOP
|
|
|
|
CONT0 JSR L03A1 ;Reset
|
|
LDX #DCB_LN
|
|
@3 LDA CNFBLK+1,X
|
|
STA CNTL_PARAM,X
|
|
DEX
|
|
BNE @3
|
|
JSR L03C9
|
|
JSR L03BE
|
|
RTS
|
|
|
|
CONT1 LDY #$00 ;Restore status table
|
|
LDA (CSLIST),Y
|
|
CMP #DCB_LN
|
|
BEQ @4
|
|
LDA #XCTLPARAM
|
|
JSR SYSERR
|
|
@4 JSR L03A1
|
|
LDY #DCB_LN
|
|
@5 LDA (CSLIST),Y
|
|
DEY
|
|
STA CNTL_PARAM+1,Y
|
|
BNE @5
|
|
JSR L03C9
|
|
JSR L03BE
|
|
RTS
|
|
|
|
CONT2 RTS ;nop
|
|
|
|
|
|
D_READ BIT OPENFLG ;check if it's open
|
|
BMI @1
|
|
JMP NOTOPEN
|
|
|
|
@1 JSR L03A1 ;set up things
|
|
LDA XPOS+1 ;is XPOS<0000?
|
|
BMI @3 ; br if so
|
|
LDX ZPD5 ;is XPOS>MAX_VIEWPORT_RIGHT?
|
|
LDA MVR_LO,X
|
|
CMP XPOS
|
|
LDA MVR_HI,X
|
|
SBC XPOS+1
|
|
BCC @3 ; br if so
|
|
LDA YPOS+1 ;is YPOS<0000?
|
|
BMI @3 ; br if so
|
|
LDA MVT_LO ;is YPOS>MAX_VIEWPORT_TOP?
|
|
CMP YPOS
|
|
LDA MVT_HI
|
|
SBC YPOS+1
|
|
BCC @3 ; br if so
|
|
LDA YPOS
|
|
JSR CALCBASE ;calc base addr
|
|
LDA XPOS
|
|
LDY XPOS+1
|
|
JSR CALCBYTE ;calc byte offset
|
|
JSR L10CB ;read color at pen position
|
|
ORA #$40 ;add 64 (it's within screen boundaries)
|
|
@2 LDY #$00 ;put char into read buffer
|
|
STA (BUFFER),Y
|
|
STY RETPTR+1
|
|
INY
|
|
STY RETPTR ;RETPTR:=$0001
|
|
JMP L03BE ;reset & leave
|
|
@3 LDA #BITON7 ;flag that pen is out of screen boundary
|
|
BNE @2 ;always
|
|
|
|
L03A1 LDX #$0E ;setup things: restore stuff to zpage
|
|
@1 LDA L00F5,X
|
|
STA ZPCA,X
|
|
DEX
|
|
BPL @1
|
|
LDX #$35
|
|
LDA #$00
|
|
@2 STA ZPC9+$1401,X
|
|
DEX
|
|
BPL @2
|
|
LDA #$8F ;X-BYTE for graphics
|
|
STA ZPCA+$1401
|
|
STA ZPCC+$1401
|
|
RTS
|
|
|
|
L03BE LDX #$0E ;reset things: save stuff from zpage
|
|
@1 LDA ZPCA,X
|
|
STA L00F5,X
|
|
DEX
|
|
BPL @1
|
|
RTS
|
|
|
|
; Verify Grafix parms (?) -- lots of jumps to here
|
|
L03C9 LDA GMODE ;filter and check out GRAFIXMODE
|
|
AND #$07
|
|
STA GMODE
|
|
TAY
|
|
AND #$03 ;filter out page bit (page 1/page 2)
|
|
STA ZPD5
|
|
TAX
|
|
LDA L0223,Y ;base addr hi-byte
|
|
STA L01B2
|
|
LDA REQD_MEM,Y
|
|
STA L01B3
|
|
LDA #$00
|
|
STA L01E6
|
|
STA L01E8
|
|
LDA #$F0
|
|
STA ZPD0
|
|
|
|
LDA F_COL ;check out FILL COLOR
|
|
ASL A
|
|
ASL A
|
|
ASL A
|
|
ASL A ;times 16
|
|
ORA F_COL ;copies low nybble into hi nybble
|
|
PHA
|
|
BEQ @1 ;branch if fill color is black
|
|
CPX #$03 ;X-reg contains GMODE
|
|
BEQ @2 ;br if GMODE=3 (140x192 full color)
|
|
DEX
|
|
TXA
|
|
BEQ @1
|
|
LDA #$FF
|
|
@1 LDX #$03
|
|
@2 TAY
|
|
LSR A
|
|
STA L01B6,X
|
|
TYA
|
|
ROR A
|
|
TAY
|
|
DEX
|
|
BPL @2
|
|
PLA
|
|
LDX ZPD5
|
|
DEX
|
|
BNE @3
|
|
STA L01B7
|
|
STA L01B9
|
|
@3 LDX #$00
|
|
STX ZPD6
|
|
STX ZPD7
|
|
STX ZPD8
|
|
|
|
LDA XFMODE ;check out transfer mode
|
|
AND #$07
|
|
STA XFMODE ;filter it
|
|
LSR A
|
|
ROR ZPD6
|
|
LSR A
|
|
ROR ZPD6
|
|
BIT ZPD6
|
|
BVC @4
|
|
BPL @4
|
|
EOR #$01
|
|
@4 LSR A
|
|
ROR ZPD7
|
|
|
|
LDA #$FF ;check out the color table
|
|
LDX #$7F
|
|
@5 LDY #$08
|
|
@6 CMP COL_TAB,X
|
|
BNE @7
|
|
DEX
|
|
DEY
|
|
BNE @6
|
|
SEC
|
|
SBC #$11
|
|
BCS @5
|
|
BCC @8 ;always
|
|
@7 LDA ZPD7
|
|
ORA #$40
|
|
STA ZPD7
|
|
|
|
@8 LDA #$00 ;check out the font
|
|
LDX #$09
|
|
@9 STA WIDTH_B,X ;width_b .. width_b+9 := 00
|
|
DEX
|
|
BPL @9
|
|
STA BYT_OFF ;set both to zero
|
|
STA BYT_OFF+1
|
|
LDA FONT_XB
|
|
STA ZPD3+$1401
|
|
LDA FONT+1 ;check if the font is the system font
|
|
CMP #$0C
|
|
BNE @10 ;is hi-byte = $0C?, br if not
|
|
LDA FONT_XB
|
|
BNE @10 ;is x-byte = $00, br if not
|
|
STA ZPD8
|
|
BNE @11 ;never branches, why is this here? bug?
|
|
LDX #$07 ;it's the system font (00:0C00), set it up
|
|
STX FWIDTH ;width := 7
|
|
INX
|
|
STX FHEIGHT ;height := 8
|
|
JMP @11
|
|
@10 LDA NOT_USED
|
|
STA ZPD8
|
|
@11 LDX FWIDTH
|
|
BEQ @12
|
|
DEX
|
|
TXA
|
|
LSR A
|
|
LSR A
|
|
LSR A
|
|
TAX
|
|
INX ;(FWIDTH-1) div 8 +1
|
|
STX WIDTH_B ; width of font in bytes
|
|
@12 LDX FHEIGHT
|
|
BEQ @14
|
|
@13 CLC ;calculate total # of bytes of
|
|
LDA WIDTH_B ; a single character
|
|
ADC BYT_OFF
|
|
STA BYT_OFF
|
|
LDA BYT_OFF+1
|
|
ADC #$00
|
|
STA BYT_OFF+1
|
|
DEX
|
|
BNE @13 ;BYT_OFF=FHEIGHT * WIDTH_B
|
|
|
|
@14 LDX #$06 ;check out the viewport definitions
|
|
L15 LDA VPORT_L+1,X
|
|
BPL @16 ;if it's negative, set it to zero
|
|
LDA #$00
|
|
STA VPORT_L,X
|
|
STA VPORT_L+1,X ;set viewport left, right, top, bott := 0000
|
|
@16 DEX
|
|
DEX
|
|
BPL L15 ;loop back
|
|
LDX #$06
|
|
LDY #$04
|
|
@17 LDA MVR_LO,Y ;is vport set beyond max size of the screen
|
|
CMP VPORT_L,X ; for this grafix mode?
|
|
LDA MVR_HI,Y
|
|
SBC VPORT_L+1,X
|
|
BCS @18
|
|
LDA MVR_LO,Y ;Yes, so set it to the max allowed
|
|
STA VPORT_L,X
|
|
LDA MVR_HI,Y
|
|
STA VPORT_L+1,X
|
|
@18 DEX
|
|
DEX
|
|
BMI @19
|
|
CPX #$04
|
|
BCS @17
|
|
LDY ZPD5
|
|
BCC @17
|
|
@19 LDX #$04
|
|
@20 LDA VPORT_R,X
|
|
CMP VPORT_L,X
|
|
LDA VPORT_R+1,X
|
|
SBC VPORT_L+1,X ;check if left & right are reversed
|
|
BCS @21 ; branch if they're OK
|
|
LDY VPORT_L,X ; otherwise, turn them around the right way
|
|
LDA VPORT_R,X
|
|
STA VPORT_L,X
|
|
TYA
|
|
STA VPORT_R,X
|
|
LDY VPORT_L+1,X
|
|
LDA VPORT_R+1,X
|
|
STA VPORT_L+1,X
|
|
TYA
|
|
STA VPORT_R+1,X
|
|
@21 DEX
|
|
DEX
|
|
DEX
|
|
DEX
|
|
BPL @20
|
|
BIT SCR_MODE
|
|
BVC @29
|
|
BMI @22
|
|
LDA $01FE ;;;;;L01FE this seems like a bug as these are absolute addresses!
|
|
AND #$DF
|
|
STA $01FE ;;;;;L01FE
|
|
JMP @29
|
|
@22 LDA $01FE ;;;;;L01FE
|
|
ORA #$20
|
|
STA $01FE ;;;;;L01FE
|
|
LDA SCR_MODE
|
|
LSR A
|
|
BCS @23
|
|
BIT SETBW ;turn on the B&W mode
|
|
BCC @24 ; always
|
|
@23 BIT SETCOL ;turn on the color mode
|
|
@24 LSR A
|
|
BCS @25
|
|
BIT COLM40 ;40 column mode
|
|
BCC @26 ; always
|
|
@25 BIT COLM80 ;80 column mode
|
|
@26 LSR A
|
|
BCS @27
|
|
BIT LOWSCR ;page one
|
|
BCC @28 ; always
|
|
@27 BIT HISCR ;page two
|
|
@28 BIT HIRES ;turn on the graphics screen
|
|
@29 RTS
|
|
|
|
|
|
D_WRITE BIT OPENFLG ;but are we open?
|
|
BMI @1 ; br if open
|
|
JMP NOTOPEN
|
|
|
|
@1 LDX GMODE
|
|
LDA MEM_FLAG ;memory allocation flag byte
|
|
CMP REQD_MEM,X ;see if proper amt of mem is allocated
|
|
BCS @2 ; br if OK
|
|
LDA #XBADMEM ;sorry, not enough memory for this mode
|
|
JSR SYSERR ; report the problem & leave
|
|
|
|
@2 JSR L03A1
|
|
LDA #$00
|
|
STA RETPTR
|
|
STA RETPTR+1
|
|
|
|
@3 LDA RETPTR+1 ;check if all the chars in
|
|
CMP REQCNT+1 ; this DßWRITE call have been
|
|
BCC @4 ; carefully scrutinized.
|
|
LDA RETPTR
|
|
CMP REQCNT ; If all finished, jump out, otherwise
|
|
BCC @4 ; branch down a few bytes.
|
|
JMP L03BE
|
|
|
|
@4 LDY #$00
|
|
LDA (BUFFER),Y ;get the next character in the buffer
|
|
INCADR BUFFER ;increment the address pointer to the next byte
|
|
INW RETPTR ;increment the # of bytes handled
|
|
JSR @5 ;check out the current character
|
|
JMP @3 ;loop back for the next character
|
|
|
|
@5 LDX CHR_TEMP
|
|
BEQ @7 ;br if a call is not currently being processed
|
|
LDY CHR_INDX ;load the index
|
|
STA CHR_BUFF-1,Y ;note: first byte stored at CHR_BUFF
|
|
INY ;incr index
|
|
TYA
|
|
CMP CALL_LEN,X ;Are all the bytes in this call present?
|
|
BCS @6 ; br if all present
|
|
STY CHR_INDX ;otherwise, store index,
|
|
RTS ; and get some more bytes
|
|
|
|
@6 LDA CHR_TEMP ;all chars present, process call
|
|
LDY #$00 ; ...but first, reset some things
|
|
STY CHR_TEMP ; for the next time around
|
|
STY CHR_INDX ;clear index & temp
|
|
JMP CON_CHR ;now -- handle the call
|
|
|
|
@7 CMP #$20 ;is it a control character?
|
|
BCC @8 ; br if so
|
|
JMP L0618 ;nope -- print the char onto the screen
|
|
|
|
@8 TAX
|
|
LDA CALL_LEN,X ;get parm length for this call
|
|
BEQ @9 ; br if this isn't a valid call -- i.e. NOP
|
|
STX CHR_TEMP ;store the cntrl char here
|
|
CMP #$01 ;parm length=1?
|
|
BEQ @6 ; br if call doesn't have any parms (go to it!)
|
|
LDA #$01
|
|
STA CHR_INDX ;initially put a one here -- used for indexing
|
|
@9 RTS
|
|
|
|
; This list contains the total length (in bytes) of each control
|
|
; character call, including the control character itself.
|
|
; Ex.: chr(00) -- 0 bytes (nop)
|
|
; chr(03) -- 6 bytes (char_set)
|
|
|
|
CALL_LEN .byte $00,$01,$09,$06,$0E,$00,$00,$00 ;chr( 0)..chr( 7)
|
|
.byte $00,$00,$01,$00,$00,$01,$01,$01 ;chr( 8)..chr(15)
|
|
.byte $02,$01,$06,$02,$02,$02,$00,$00 ;chr(16)..chr(23)
|
|
.byte $05,$05,$05,$00,$01,$00,$00,$00 ;chr(24)..chr(31)
|
|
|
|
; set up to put a character on the graphics screen
|
|
L0618 CMP #$A0
|
|
BCS @1 ; br is char >= $A0
|
|
CMP #$80
|
|
BCC @1 ; br if char < $80
|
|
AND #$7F ;clear hi-bit
|
|
@1 LDX FWIDTH ;copy font info into temp locations
|
|
STX L01DD+5
|
|
LDX FHEIGHT
|
|
STX L01DD+7
|
|
LDX #$00
|
|
STX L01DD+6
|
|
STX L01DD+8
|
|
LDX FONT ;copy font addrs into z-page locations
|
|
STX ZPD3
|
|
LDX FONT+1
|
|
STX ZPD4
|
|
LDX FONT_XB
|
|
STX ZPD3+$1401
|
|
TAX
|
|
BEQ @4
|
|
|
|
@2 CLC
|
|
LDA ZPD3 ;set up addr of font character
|
|
ADC BYT_OFF ;char_addr:= base_addr + (char# * byte_offset)
|
|
STA ZPD3
|
|
LDA ZPD4
|
|
ADC BYT_OFF+1
|
|
STA ZPD4
|
|
BCC @3
|
|
INC ZPD3+$1401
|
|
INC ZPD3+$1401
|
|
@3 DEX
|
|
BNE @2
|
|
@4 JSR PUTres ;put font char on screen
|
|
CLC ;update X & Y position after
|
|
LDA XPOS ; putting char on screen
|
|
ADC FWIDTH
|
|
STA XPOS
|
|
LDA XPOS+1
|
|
ADC #$00
|
|
STA XPOS+1
|
|
RTS
|
|
|
|
; Handle those control characters....
|
|
CON_CHR SWITCH ,,CHARS
|
|
|
|
CHARS .word CHR_NOP-1
|
|
.word RSTVIEW-1 ;01 Reset Viewport
|
|
.word SETVIEW-1 ;02 Set Viewport
|
|
.word CHARSET-1 ;03 Character Set
|
|
.word DRAWBLK-1 ;04 Drawres
|
|
.word CHR_NOP-1
|
|
.word CHR_NOP-1
|
|
.word CHR_NOP-1
|
|
.word CHR_NOP-1
|
|
.word CHR_NOP-1
|
|
.word MOV_PDN-1 ;10. Move Pen Down (LF)
|
|
.word CHR_NOP-1
|
|
.word CHR_NOP-1
|
|
.word RET_PEN-1 ;13. Return Pen (CR)
|
|
.word SCRNOFF-1 ;14. Turn Graphics Screen Off
|
|
.word SCRN_ON-1 ;15. Turn Graphics Screen On
|
|
.word SETMODE-1 ;16. Set Graphics Mode
|
|
.word RSTCOLT-1 ;17. Reset Color Operator Table
|
|
.word SETCOLT-1 ;18. Set Color Operator Table
|
|
.word SETPCOL-1 ;19. Set Pen Color
|
|
.word SETFCOL-1 ;20. Set Fill Color
|
|
.word SETXMOD-1 ;21. Set Transfer Mode
|
|
.word CHR_NOP-1
|
|
.word CHR_NOP-1
|
|
.word LINE_TO-1 ;24. Draw Line to X,Y
|
|
.word DOT_AT-1 ;25. Plot Point at X,Y
|
|
.word MOVE_TO-1 ;26. Move Pen to X,Y
|
|
.word CHR_NOP-1
|
|
.word CLRVIEW-1 ;28. Clear Viewport
|
|
.word CHR_NOP-1
|
|
.word CHR_NOP-1
|
|
.word CHR_NOP-1
|
|
|
|
CHR_NOP RTS
|
|
|
|
SETMODE LDA CHR_BUFF ;set graphics mode
|
|
STA GMODE
|
|
JMP L03C9
|
|
|
|
SETXMOD LDA CHR_BUFF ;set transfer mode
|
|
STA XFMODE
|
|
JMP L03C9
|
|
|
|
SCRNOFF LDA GMODE ;turn screen off
|
|
AND #$07
|
|
ORA #$40
|
|
STA SCR_MODE
|
|
JMP L03C9
|
|
|
|
SCRN_ON LDA GMODE ;enable graphics mode
|
|
AND #$07
|
|
ORA #$C0
|
|
STA SCR_MODE
|
|
JMP L03C9
|
|
|
|
MOV_PDN SEC ;move pen down (LF)
|
|
LDA YPOS ;subtract font height from the
|
|
SBC FHEIGHT ; current x,y position
|
|
STA YPOS
|
|
LDA YPOS+1
|
|
SBC #$00
|
|
STA YPOS+1
|
|
RTS
|
|
|
|
RET_PEN LDA VPORT_L ;return pen (CR)
|
|
STA XPOS ;set x position to the left
|
|
LDA VPORT_L+1 ; viewport edge
|
|
STA XPOS+1
|
|
RTS
|
|
|
|
CHARSET LDX #$04 ;character set
|
|
@1 LDA CHR_BUFF,X ;store chacter set address
|
|
STA FONT,X
|
|
DEX
|
|
BPL @1
|
|
JMP L03C9
|
|
|
|
RSTVIEW LDX ZPD5 ;reset viewport
|
|
LDA #$00
|
|
STA VPORT_L
|
|
STA VPORT_L+1
|
|
STA VPORT_B
|
|
STA VPORT_B+1 ;left & bottom := 0
|
|
LDA MVR_LO,X
|
|
STA VPORT_R ;viewport-right := max right value
|
|
LDA MVR_HI,X
|
|
STA VPORT_R+1
|
|
LDA MVT_LO ;viewport-top := max top value
|
|
STA VPORT_T
|
|
LDA MVT_HI
|
|
STA VPORT_T+1
|
|
RTS
|
|
|
|
SETVIEW LDX #$08 ;set viewport
|
|
@1 LDA CHR_BUFF-1,X
|
|
STA VPORT_L-1,X
|
|
DEX
|
|
BNE @1
|
|
JMP L03C9
|
|
|
|
RSTCOLT LDX #$7F ;reset color table
|
|
@1 LDA COLT2,X
|
|
STA COL_TAB,X
|
|
DEX
|
|
BPL @1
|
|
JMP L03C9
|
|
|
|
SETCOLT LDA CHR_BUFF+4 ;set color table
|
|
AND #$0F
|
|
STA CHR_BUFF+4
|
|
ASL A
|
|
ASL A
|
|
ASL A
|
|
ASL A
|
|
ORA CHR_BUFF+4
|
|
STA CHR_BUFF+4
|
|
CLV
|
|
LDX #$0F
|
|
LDA CHR_BUFF
|
|
@1 ASL A
|
|
BCC @7
|
|
PHA
|
|
LDY #$0F
|
|
LDA CHR_BUFF+2
|
|
@2 ASL A
|
|
BCC @5
|
|
PHA
|
|
STY CHR_BUFF
|
|
TXA
|
|
PHA
|
|
ASL A
|
|
ASL A
|
|
ASL A
|
|
LSR CHR_BUFF
|
|
ORA CHR_BUFF
|
|
TAX
|
|
LDA COL_TAB,X
|
|
EOR CHR_BUFF+4
|
|
BCS @3
|
|
AND #$0F
|
|
BCC @4
|
|
@3 AND #$F0
|
|
@4 EOR CHR_BUFF+4
|
|
STA COL_TAB,X
|
|
PLA
|
|
TAX
|
|
PLA
|
|
@5 DEY
|
|
BMI @6
|
|
CPY #$07
|
|
BNE @2
|
|
LDA CHR_BUFF+3
|
|
BVC @2
|
|
@6 PLA
|
|
@7 DEX
|
|
BMI @8
|
|
CPX #$07
|
|
BNE @1
|
|
LDA CHR_BUFF+1
|
|
BVC @1
|
|
@8 JMP L03C9
|
|
|
|
SETPCOL LDA CHR_BUFF ;set pen color
|
|
AND #$0F
|
|
STA PN_COL
|
|
RTS
|
|
|
|
SETFCOL LDA CHR_BUFF ;set fill color
|
|
AND #$0F
|
|
STA F_COL
|
|
JMP L03C9
|
|
|
|
MOVE_TO LDX #$03 ;move to
|
|
@1 LDA CHR_BUFF,X
|
|
STA XPOS,X
|
|
DEX
|
|
BPL @1
|
|
RTS
|
|
|
|
DOT_AT LDX #$03 ;dot at
|
|
@1 LDA CHR_BUFF,X
|
|
STA XPOS,X
|
|
STA ZPF5,X ; ZPF5..ZPF8
|
|
STA ZPF0,X ; ZPF0..ZPF3
|
|
DEX
|
|
BPL @1
|
|
JSR L0C21 ;out of bounds?
|
|
BCS @2 ;yep. Don't bother displaying it
|
|
JMP L0F9D ;Display it
|
|
@2 RTS
|
|
|
|
LINE_TO LDX #$03 ;line to
|
|
@1 LDA XPOS,X
|
|
STA ZPF0,X ; ZPF0..ZPF3
|
|
LDA CHR_BUFF,X
|
|
STA XPOS,X
|
|
STA ZPF5,X ; ZPF5..ZPF8
|
|
DEX
|
|
BPL @1
|
|
JSR L0C21
|
|
BCS @2
|
|
JSR L0F9D
|
|
JMP L0F02
|
|
@2 RTS
|
|
|
|
CLRVIEW LDX #$0A ;clear viewport
|
|
@1 LDA ZPCA,X
|
|
PHA
|
|
DEX
|
|
BPL @1
|
|
LDA #$F0
|
|
STA L01E6
|
|
LDA VPORT_T
|
|
JSR CALCBASE ;calc base addr
|
|
SEC
|
|
LDA VPORT_T
|
|
SBC VPORT_B
|
|
STA ZPE8
|
|
INC ZPE8
|
|
LDA #$00
|
|
STA ZPF5
|
|
STA ZPF6
|
|
LDA VPORT_L
|
|
LDY VPORT_L+1
|
|
JSR CALCBYTE ;calc byte offset
|
|
STA ZPF2
|
|
LDX ZPD5
|
|
CPX #$03
|
|
BEQ @2
|
|
LDA #$0F
|
|
STA ZPD0
|
|
@2 LDX #$04
|
|
@3 LDA ZPCE,X
|
|
STA ZPE9,X
|
|
DEX
|
|
BPL @3
|
|
LDA ZPD7
|
|
ORA ZPD6
|
|
BEQ @5
|
|
CLC
|
|
LDA VPORT_L
|
|
SBC VPORT_R
|
|
STA ZPF3
|
|
LDA VPORT_L+1
|
|
SBC VPORT_R+1
|
|
STA ZPF4
|
|
DEC ZPF3
|
|
BNE @4
|
|
DEC ZPF4
|
|
@4 JMP CL19 ; (@19)
|
|
|
|
@5 STX ZPF3
|
|
STX ZPF4
|
|
LDA ZPCF
|
|
LDX ZPD5
|
|
CPX #$03
|
|
BNE @6
|
|
EOR #$0F
|
|
@6 CMP #$02
|
|
JSR CL29 ; (@29)
|
|
BEQ @9
|
|
INC ZPF2
|
|
AND #$03
|
|
LSR A
|
|
BNE @7
|
|
INC ZPF2
|
|
@7 ROL A
|
|
JSR CL30 ; (@30)
|
|
EOR #$FF
|
|
STA ZPF3
|
|
TXA
|
|
LDX #$15
|
|
CMP #$03
|
|
BNE @8
|
|
LDX #$07
|
|
@8 DEX
|
|
DEC ZPF3
|
|
LDA L023A,X
|
|
CMP ZPCF
|
|
BNE @8
|
|
LDA L0233,X
|
|
CMP ZPD0
|
|
BNE @8
|
|
@9 LDA VPORT_R
|
|
LDY VPORT_R+1
|
|
JSR CALCBYTE ;calc byte offset
|
|
STA ZPF7
|
|
LDX ZPD5
|
|
CPX #$02
|
|
BEQ @10
|
|
SEC
|
|
ROR ZPD2
|
|
@10 CPX #$03
|
|
BCC @11
|
|
LDA ZPD0
|
|
CMP #$78
|
|
JMP @12
|
|
|
|
@11 LDA ZPCF
|
|
CMP #$40
|
|
@12 JSR CL29 ; (@29)
|
|
EOR #$07
|
|
TAY
|
|
BNE @13
|
|
INC ZPF7
|
|
BPL @14
|
|
@13 AND #$02
|
|
BNE @14
|
|
DEC ZPF7
|
|
@14 TYA
|
|
BEQ @16
|
|
AND #$03
|
|
JSR CL30 ; (@30)
|
|
STA ZPF6
|
|
TXA
|
|
LDX #$0D
|
|
CMP #$03
|
|
BNE @15
|
|
LDX #$FF
|
|
@15 INX
|
|
INC ZPF6
|
|
LDA L023A,X
|
|
CMP ZPCF
|
|
BNE @15
|
|
LDA L0233,X
|
|
CMP ZPD0
|
|
BNE @15
|
|
@16 SEC
|
|
LDA ZPF7
|
|
SBC ZPF2
|
|
BMI @17
|
|
LSR A
|
|
STA ZPF5
|
|
BNE CL19 ; (@19)
|
|
SEC
|
|
LDA ZPF3
|
|
BCS @18
|
|
@17 LDA ZPF3
|
|
LDX ZPD5
|
|
ADC L0254,X
|
|
@18 SBC ZPF6
|
|
STA ZPF3
|
|
LDA #$00
|
|
STA ZPF6
|
|
CL19 LDX #$04
|
|
@20 LDA ZPF3,X
|
|
STA ZPEE,X
|
|
LDA ZPE9,X
|
|
STA ZPCE,X
|
|
DEX
|
|
BPL @20
|
|
TAY
|
|
@21 INC ZPEE
|
|
BNE @22
|
|
INC ZPEF
|
|
BNE @22
|
|
JMP @23
|
|
|
|
@22 JSR L09B6
|
|
JMP @21
|
|
|
|
@23 DEC ZPF0
|
|
BMI @25
|
|
LDX #$00
|
|
@24 LDA L01B6,X
|
|
STA (ZPCA),Y
|
|
LDA L01B7,X
|
|
STA (ZPCC),Y
|
|
INY
|
|
INX
|
|
INX
|
|
CPX #$02
|
|
BEQ @24
|
|
BNE @23 ;always
|
|
|
|
@25 STY ZPCE
|
|
DEC ZPF1
|
|
BMI @26
|
|
JSR L09B6
|
|
JMP @25
|
|
|
|
@26 DEC ZPE8
|
|
BEQ @27
|
|
JSR L0E16
|
|
JMP CL19
|
|
|
|
@27 LDX #$00
|
|
@28 PLA
|
|
STA ZPCA,X
|
|
INX
|
|
CPX #$0B
|
|
BNE @28
|
|
LDA #$00
|
|
STA L01E6
|
|
RTS
|
|
|
|
CL29 ROL A
|
|
ROR ZPCE
|
|
ROL A
|
|
ROL ZPD2
|
|
ROL A
|
|
AND #$07
|
|
RTS
|
|
|
|
CL30 TAY
|
|
CPX #$02
|
|
BEQ @31
|
|
LDY #$03
|
|
BCS @31
|
|
CMP #$02
|
|
BCS @31
|
|
DEY
|
|
@31 LDA L0250,Y
|
|
RTS
|
|
|
|
L09B6 JSR L0FAA
|
|
JSR L0EA7
|
|
RTS
|
|
|
|
DRAWBLK LDA ZPD8
|
|
PHA
|
|
LDA NOT_USED
|
|
STA ZPD8
|
|
LDX #$09
|
|
@1 LDA WIDTH_B,X
|
|
PHA
|
|
LDA CHR_BUFF+3,X
|
|
STA WIDTH_B,X
|
|
DEX
|
|
BPL @1
|
|
LDA CHR_BUFF
|
|
STA ZPD3
|
|
LDA CHR_BUFF+1
|
|
STA ZPD4
|
|
LDA CHR_BUFF+2
|
|
STA ZPD3+$1401
|
|
JSR PUTres ;put res onto graphics screen
|
|
LDX #$00
|
|
@2 PLA
|
|
STA WIDTH_B,X
|
|
INX
|
|
CPX #$0A
|
|
BCC @2
|
|
PLA
|
|
STA ZPD8
|
|
RTS
|
|
|
|
; =====================================================================
|
|
;
|
|
; HARDWARE SPECIFIC CODES FOLLOWS....
|
|
;
|
|
; =====================================================================
|
|
|
|
PUTres ;put character/res onto graphics screen
|
|
LDX #$03
|
|
LDA #$F0
|
|
STA L01E8
|
|
@4 LDA XPOS,X
|
|
STA ZPF5,X
|
|
DEX
|
|
BPL @4
|
|
SEC
|
|
LDA VPORT_L
|
|
SBC ZPF5
|
|
STA ZPD9
|
|
LDA VPORT_L+1
|
|
SBC ZPF6
|
|
STA ZPDA
|
|
BMI @5
|
|
SEC
|
|
LDA L01DD+5
|
|
SBC ZPD9
|
|
STA L01DD+5
|
|
LDA L01DD+6
|
|
SBC ZPDA
|
|
STA L01DD+6
|
|
BMI @7
|
|
LDA VPORT_L
|
|
STA ZPF5
|
|
LDA VPORT_L+1
|
|
STA ZPF6
|
|
BIT ZPD8
|
|
BPL @5
|
|
CLC
|
|
LDA L01DD+1
|
|
ADC ZPD9
|
|
STA L01DD+1
|
|
LDA L01DD+2
|
|
ADC ZPDA
|
|
STA L01DD+2 ;(L01DD+1):=(L01DD+1)+ZPD9
|
|
@5 CLC
|
|
LDA ZPF5
|
|
ADC L01DD+5
|
|
STA ZPD9
|
|
LDA ZPF6
|
|
ADC L01DD+6
|
|
STA ZPDA
|
|
SEC
|
|
LDA ZPD9
|
|
SBC VPORT_R
|
|
STA ZPD9
|
|
LDA ZPDA
|
|
SBC VPORT_R+1
|
|
STA ZPDA
|
|
BMI @8
|
|
INC L01DD+5
|
|
BNE @6
|
|
INC L01DD+6
|
|
@6 SEC
|
|
LDA L01DD+5
|
|
SBC ZPD9
|
|
STA L01DD+5
|
|
LDA L01DD+6
|
|
SBC ZPDA
|
|
STA L01DD+6
|
|
BPL @8
|
|
@7 RTS
|
|
|
|
@8 SEC
|
|
LDA ZPF7
|
|
SBC VPORT_T
|
|
STA ZPD9
|
|
LDA ZPF8
|
|
SBC VPORT_T+1
|
|
STA ZPDA
|
|
BMI @10
|
|
SEC
|
|
LDA L01DD+7
|
|
SBC ZPD9
|
|
STA L01DD+7
|
|
LDA L01DD+8
|
|
SBC ZPDA
|
|
STA L01DD+8
|
|
BMI @7
|
|
BNE @9
|
|
LDA L01DD+7
|
|
BEQ @7
|
|
@9 LDA VPORT_T
|
|
STA ZPF7
|
|
LDA VPORT_T+1
|
|
STA ZPF8
|
|
CLC
|
|
LDA L01DD+3
|
|
ADC ZPD9
|
|
STA L01DD+3
|
|
LDA L01DD+4
|
|
ADC ZPDA
|
|
STA L01DD+4
|
|
@10 SEC
|
|
LDA ZPF7
|
|
SBC VPORT_B
|
|
STA ZPE8
|
|
LDA ZPF8
|
|
SBC VPORT_B+1
|
|
STA ZPE9
|
|
BMI @7
|
|
SEC
|
|
LDA ZPF7
|
|
SBC L01DD+7
|
|
STA ZPD9
|
|
LDA ZPF8
|
|
SBC L01DD+8
|
|
STA ZPDA
|
|
SEC
|
|
LDA ZPD9
|
|
SBC VPORT_B
|
|
STA ZPD9
|
|
LDA ZPDA
|
|
SBC VPORT_B+1
|
|
STA ZPDA
|
|
BPL @11
|
|
INC ZPE8
|
|
BNE @12
|
|
@11 SEC
|
|
LDA ZPE8
|
|
SBC ZPD9
|
|
STA ZPE8
|
|
LDA ZPE9
|
|
SBC ZPDA
|
|
STA ZPE9
|
|
@12 LDX #$0A
|
|
@13 LDA ZPCA,X
|
|
PHA
|
|
DEX
|
|
BPL @13
|
|
LDA ZPF7
|
|
JSR CALCBASE ;calc base addr
|
|
LDA ZPF5
|
|
LDY ZPF6
|
|
JSR CALCBYTE ;calc byte offset
|
|
LDX #$04
|
|
@14 LDA ZPCE,X
|
|
STA ZPE9,X
|
|
DEX
|
|
BPL @14
|
|
CLC
|
|
LDA L01DD+1
|
|
ADC L01DD+5
|
|
STA ZPD9
|
|
LDA L01DD+2
|
|
ADC L01DD+6
|
|
STA ZPDA
|
|
LDA L01DD+1
|
|
AND #$07
|
|
STA ZPEF
|
|
LDA ZPD9
|
|
AND #$07
|
|
STA ZPF1
|
|
LDA L01DD+1
|
|
ROR L01DD+2
|
|
ROR A
|
|
ROR L01DD+2
|
|
ROR A
|
|
ROR L01DD+2
|
|
ROR A
|
|
STA ZPEE
|
|
LDA ZPD9
|
|
ROR ZPDA
|
|
ROR A
|
|
ROR ZPDA
|
|
ROR A
|
|
ROR ZPDA
|
|
ROR A
|
|
STA ZPF0
|
|
DB15 LDA L01DD+3
|
|
BNE @16
|
|
LDA L01DD+4
|
|
BEQ @18
|
|
@16 CLC
|
|
LDA ZPD3
|
|
ADC WIDTH_B
|
|
STA ZPD3
|
|
LDA ZPD4
|
|
ADC L01DD
|
|
STA ZPD4
|
|
BCC @17
|
|
INC ZPD3+$1401
|
|
INC ZPD3+$1401
|
|
@17 LDA L01DD+3
|
|
SEC
|
|
SBC #$01
|
|
STA L01DD+3
|
|
LDA L01DD+4
|
|
SBC #$00
|
|
STA L01DD+4
|
|
JMP DB15
|
|
|
|
@18 LDX #$04
|
|
@19 LDA ZPE9,X
|
|
STA ZPCE,X
|
|
DEX
|
|
BPL @19
|
|
LDY ZPEE
|
|
STY ZPF2
|
|
LDA (ZPD3),Y
|
|
LDX #$00
|
|
@20 CPX ZPEF
|
|
BEQ @21
|
|
ASL A
|
|
INX
|
|
BNE @20
|
|
@21 STA ZPF4
|
|
@22 STX ZPF3
|
|
CPX ZPF1
|
|
BNE @23
|
|
LDA ZPF2
|
|
CMP ZPF0
|
|
BEQ @27
|
|
@23 LDY ZPCE
|
|
BIT ZPD8
|
|
BMI @24
|
|
LSR ZPF4
|
|
BPL @25
|
|
@24 ASL ZPF4
|
|
@25 LDA #$00
|
|
BCS @26
|
|
LDA #$F0
|
|
@26 STA L01E6
|
|
JSR L09B6
|
|
LDX ZPF3
|
|
INX
|
|
CPX #$08
|
|
BNE @22
|
|
LDX #$00
|
|
INC ZPF2
|
|
LDY ZPF2
|
|
LDA (ZPD3),Y
|
|
STA ZPF4
|
|
JMP @22
|
|
|
|
@27 DEC ZPE8
|
|
BEQ @29
|
|
JSR L0E16
|
|
CLC
|
|
LDA ZPD3
|
|
ADC WIDTH_B
|
|
STA ZPD3
|
|
LDA ZPD4
|
|
ADC L01DD
|
|
STA ZPD4
|
|
BCC @28
|
|
INC ZPD3+$1401
|
|
INC ZPD3+$1401
|
|
@28 JMP @18
|
|
|
|
@29 LDX #$00
|
|
@30 PLA
|
|
STA ZPCA,X
|
|
INX
|
|
CPX #$0B
|
|
BNE @30
|
|
LDA #$00
|
|
STA L01E6
|
|
STA L01E8
|
|
RTS
|
|
|
|
; See "Principles of Interactive Computer Graphics", second edition
|
|
; Newman & Sproull, pages 65-68
|
|
|
|
L0C21 LDY #$0F
|
|
JSR L0D00 ;check bounds
|
|
STA ZPF4
|
|
LDY #$14
|
|
JSR L0D00 ;check bounds
|
|
STA ZPF9
|
|
@1 LDA ZPF9
|
|
ORA ZPF4
|
|
AND #$0F
|
|
BNE @2
|
|
CLC ;both endpoints are within the viewport
|
|
RTS
|
|
|
|
@2 LDA ZPF4
|
|
AND ZPF9
|
|
AND #$0F
|
|
BEQ @4
|
|
SEC ;both endpoints are outside viewport and the
|
|
@3 RTS ; line does not enter viewport
|
|
|
|
@4 LDA ZPF4 ;both endpoints outside, but check if the
|
|
AND #$0F ; line crosses into the viewport
|
|
BEQ @5
|
|
LDX #$00
|
|
LDY #$0F
|
|
JSR L0D59 ;copy
|
|
LDX #$05
|
|
LDY #$14
|
|
JSR L0D59 ;copy
|
|
JSR @6 ;midpoint subdivision
|
|
BCS @3
|
|
LDX #$0F
|
|
LDY #$0A
|
|
JSR L0D59 ;copy
|
|
BEQ @1
|
|
@5 LDA ZPF9
|
|
AND #$0F
|
|
BEQ @1
|
|
LDX #$00
|
|
LDY #$14
|
|
JSR L0D59 ;copy
|
|
LDX #$05
|
|
LDY #$0F
|
|
JSR L0D59
|
|
JSR @6
|
|
BCS @3
|
|
LDX #$14
|
|
LDY #$0A
|
|
JMP L0D59
|
|
|
|
; ---- Mid-Point Subdivision ----
|
|
@6 LDA ZPE5 ;border bits (from)
|
|
EOR ZPEA ; (to)
|
|
AND ZPE5
|
|
ASL A
|
|
ASL A
|
|
ASL A
|
|
ASL A ;mul 16 (move lo nybble to hi)
|
|
STA ZPDF
|
|
AND ZPEA
|
|
BEQ @8 ;br to try it out
|
|
LDA ZPEA
|
|
AND #$0F
|
|
BNE @7 ;br if it's completely outside
|
|
LDX #$0A
|
|
LDY #$05
|
|
CLC
|
|
JMP L0D59
|
|
|
|
@7 SEC ;completely outside viewport
|
|
RTS
|
|
|
|
@8 STA ZPDB
|
|
STA ZPDD
|
|
|
|
@9 ROL ZPDB
|
|
LDA ZPE1 ;XPOS (from)
|
|
ADC ZPE6 ;XPOS (to)
|
|
STA ZPEB
|
|
LDA ZPE2 ;XPOS+1 (from)
|
|
ADC ZPE7 ;XPOS+1 (to)
|
|
BVS @10
|
|
CMP #$80
|
|
@10 ROR A ;div 2
|
|
STA ZPEC
|
|
ROR ZPEB ;div 2
|
|
ROR ZPDB
|
|
ROL ZPDD
|
|
LDA ZPE3 ;YPOS (from)
|
|
ADC ZPE8 ;YPOS (to)
|
|
STA ZPED
|
|
LDA ZPE4 ;YPOS+1 (from)
|
|
ADC ZPE9 ;YPOS+1 (to)
|
|
BVS @11
|
|
CMP #$80
|
|
@11 ROR A ;div 2
|
|
STA ZPEE
|
|
ROR ZPED ;div 2
|
|
ROR ZPDD
|
|
LDY #$0A
|
|
JSR L0D00 ;check if the midpoint is inside vport
|
|
STA ZPEF
|
|
AND ZPE5
|
|
AND #$0F
|
|
BEQ @13 ;br if inside viewport
|
|
LDX #$00
|
|
JSR L0D59
|
|
LDA ZPE5
|
|
AND ZPEA
|
|
AND #$0F
|
|
BEQ @9
|
|
@12 CLC ;completely inside viewport
|
|
RTS
|
|
|
|
@13 LDA ZPEF
|
|
AND ZPDF
|
|
BNE @12 ;all done
|
|
LDX #$05
|
|
JSR L0D59
|
|
BEQ @9 ;go around for another try
|
|
|
|
; CHECK VIEWPORT BOUNDS inside outside
|
|
; bit # 7 6 5 4 3 2 1 0
|
|
; leaves flag in acc -> T B R L T B R L
|
|
|
|
L0D00 LDA #$00 ;check viewport bounds
|
|
LDX ZPE2,Y ;XPOS+1
|
|
BMI @6 ; br if neg -- outside viewport
|
|
CPX VPORT_L+1
|
|
BCC @6 ; br if VPORT_L+1>XPOS+1
|
|
BNE @2 ; br if not equal
|
|
LDX ZPE1,Y ;XPOS
|
|
CPX VPORT_L
|
|
BCC @6 ; br if VPORT_L>XPOS
|
|
BEQ @5 ; br if equal
|
|
@1 LDX ZPE2,Y ;XPOS+1
|
|
@2 CPX VPORT_R+1
|
|
BCC @7 ; br if VPORT_R+1>XPOS+1
|
|
BNE @3 ; br if not equal
|
|
LDX ZPE1,Y ;XPOS
|
|
CPX VPORT_R
|
|
BCC @7 ; br if VPORT_R>XPOS
|
|
BEQ @4 ; br if equal
|
|
@3 ORA #BITON1 ;outside of the right edge
|
|
BNE @7 ; always
|
|
@4 ORA #BITON5 ;inside of the right edge
|
|
BNE @7 ; always
|
|
@5 ORA #BITON4 ;inside of the left edge
|
|
BNE @1 ; always -- go check right edge
|
|
@6 ORA #BITON0 ;outside of the left edge
|
|
@7 LDX ZPE4,Y ;YPOS+1
|
|
BMI @12 ; br if neg -- outside
|
|
BNE @9 ; br if hi-byte is not zero -- outside
|
|
LDX ZPE3,Y ;YPOS
|
|
CPX VPORT_B
|
|
BCC @12
|
|
BEQ @11
|
|
@8 CPX VPORT_T
|
|
BEQ @10 ; br if equal
|
|
BCC @13 ; br if VPORT_T>YPOS
|
|
@9 ORA #BITON3 ;above top edge (outside)
|
|
RTS
|
|
|
|
@10 ORA #BITON7 ;at top edge (inside)
|
|
RTS
|
|
|
|
@11 ORA #BITON6 ;at bottom edge (inside)
|
|
BNE @8 ; br always -- go check top edge
|
|
@12 ORA #BITON2 ;below bottom edge (outside)
|
|
@13 RTS
|
|
|
|
L0D59 LDA #$05
|
|
STA ZPE0
|
|
@1 LDA ZPE1,Y
|
|
STA ZPE1,X
|
|
INX
|
|
INY
|
|
DEC ZPE0
|
|
BNE @1
|
|
RTS
|
|
|
|
CALCBASE ;Calculate base address -- ACC:=YPOS
|
|
STA ZPD9
|
|
SEC
|
|
LDA #$BF
|
|
SBC ZPD9
|
|
TAY
|
|
LSR A
|
|
LSR A
|
|
LSR A ;div 8
|
|
TAX
|
|
TYA
|
|
ASL A
|
|
ASL A ;mul 4
|
|
AND #$1C
|
|
ORA L01F3,X
|
|
TAY
|
|
ORA L01B2
|
|
STA ZPCB
|
|
TYA
|
|
ORA L01B3
|
|
STA ZPCD
|
|
LDA L020B,X
|
|
STA ZPCA
|
|
STA ZPCC
|
|
STX ZPE7
|
|
RTS
|
|
|
|
CALCBYTE ;Calculate byte offset -- ACC:=XPOS, Y_REG:=XPOS+1
|
|
SEC
|
|
BEQ @3 ; br if XPOS+1=00
|
|
DEY
|
|
BEQ @1
|
|
LDY #$48 ;gets here when X_HI=2
|
|
ADC #$01
|
|
BCC @2 ; br if XPOS<=255
|
|
@1 LDY #$23 ;gets here when X_HI=1
|
|
ADC #$04
|
|
BCC @2
|
|
INY
|
|
SBC #$07
|
|
@2 INY
|
|
@3 SBC #$07 ; DIV 7 -- the old-fashioned way
|
|
BCS @2
|
|
TAX ; remainder into X
|
|
TYA
|
|
LDY COL_TAB+$35,X
|
|
STY ZPCF
|
|
LDY ZPD5
|
|
CPY #$02
|
|
STY ZPD2
|
|
BCC @4
|
|
BEQ @5
|
|
ASL A
|
|
LDY COL_TAB+$20,X
|
|
STY ZPD0
|
|
LDY COL_TAB+$27,X
|
|
STY ZPCF
|
|
STX ZPD1 ;remainder (in 2's complement form)
|
|
CPX #$FC
|
|
ADC #$00
|
|
@4 STA ZPCE ;byte offset
|
|
RTS ; something get left in ACC
|
|
|
|
@5 LSR A
|
|
STA ZPCE ;byte offset
|
|
ROR ZPD2
|
|
RTS
|
|
|
|
L0DD8 BPL L0E16
|
|
CLC
|
|
LDA ZPCB
|
|
BIT L025A
|
|
BNE L0E08
|
|
ASL ZPCA
|
|
BCS L0E00
|
|
BIT L0258
|
|
BEQ L0DF0
|
|
ADC #$1F
|
|
SEC
|
|
BCS L0E02
|
|
L0DF0 ADC #$23
|
|
PHA
|
|
LDA ZPCA
|
|
ADC #$B0
|
|
BCS L0DFB
|
|
ADC #$F0
|
|
L0DFB STA ZPCA
|
|
PLA
|
|
BCS L0E02
|
|
L0E00 ADC #$1F
|
|
L0E02 ROR ZPCA
|
|
LDX ZPCA
|
|
STX ZPCC
|
|
L0E08 ADC #$FC
|
|
L0E0A STA ZPCB
|
|
AND #$1F
|
|
STA ZPE7
|
|
ORA L01B3
|
|
STA ZPCD
|
|
RTS
|
|
|
|
L0E16 CLC
|
|
LDA ZPCB
|
|
ADC #$04
|
|
BIT L025A
|
|
BNE L0E0A
|
|
ASL ZPCA
|
|
BCC L0E3E
|
|
ADC #$E0
|
|
CLC
|
|
BIT L0259
|
|
BEQ L0E40
|
|
LDA ZPCA
|
|
ADC #$50
|
|
EOR #$F0
|
|
BEQ L0E36
|
|
EOR #$F0
|
|
L0E36 STA ZPCA
|
|
LDA ZPCB
|
|
AND #$E0
|
|
BCC L0E40
|
|
L0E3E ADC #$E0
|
|
L0E40 ROR ZPCA
|
|
LDX ZPCA
|
|
STX ZPCC
|
|
BCC L0E0A
|
|
L0E48 BVS L0E4D
|
|
JMP L0EA7
|
|
|
|
L0E4D LDX ZPD5
|
|
CPX #$02
|
|
BEQ L0E6B
|
|
BCS L0E84
|
|
LSR ZPCF
|
|
BCC L0E6A
|
|
DEY
|
|
BPL L0E64
|
|
L0E5C ROL ZPCF
|
|
INY
|
|
STY ZPCE
|
|
RTS
|
|
|
|
L0E62 LDY #$27
|
|
L0E64 LDA #$40
|
|
STA ZPCF
|
|
STY ZPCE
|
|
L0E6A RTS
|
|
|
|
L0E6B LSR ZPCF
|
|
BCC L0E6A
|
|
LDA #$40
|
|
STA ZPCF
|
|
ASL A
|
|
EOR ZPD2
|
|
STA ZPD2
|
|
BPL L0E6A
|
|
DEY
|
|
STY ZPCE
|
|
BPL L0E6A
|
|
LSR ZPD2
|
|
SEC
|
|
BCS L0E5C
|
|
L0E84 LDX ZPD1
|
|
CPX #$FC
|
|
BNE L0E8B
|
|
DEY
|
|
L0E8B DEX
|
|
CPX #$F9
|
|
BCS L0E98
|
|
LDX #$FF
|
|
DEY
|
|
BPL L0E98
|
|
INY
|
|
LDX #$F9
|
|
L0E98 STY ZPCE
|
|
STX ZPD1
|
|
LDA COL_TAB+$27,X
|
|
STA ZPCF
|
|
LDA COL_TAB+$20,X
|
|
STA ZPD0
|
|
RTS
|
|
|
|
L0EA7 LDX ZPD5
|
|
CPX #$02
|
|
BEQ @3
|
|
BCS @4
|
|
ASL ZPCF
|
|
BPL @2
|
|
INY
|
|
CPY #$28
|
|
BCC @1
|
|
JMP L0E62
|
|
|
|
@1 LDA #$01
|
|
STA ZPCF
|
|
STY ZPCE
|
|
@2 RTS
|
|
|
|
@3 ASL ZPCF
|
|
BPL @2
|
|
LDA #$01
|
|
STA ZPCF
|
|
LDA #$FF
|
|
EOR ZPD2
|
|
STA ZPD2
|
|
BMI @2
|
|
INY
|
|
STY ZPCE
|
|
CPY #$28
|
|
BCC @2
|
|
ROR ZPD2
|
|
JMP L0E62
|
|
|
|
@4 LDX ZPD1
|
|
CPX #$FB
|
|
BNE @5
|
|
INY
|
|
@5 INX
|
|
BNE @6
|
|
LDX #$F9
|
|
INY
|
|
CPY #$28
|
|
BCC @6
|
|
LDX #$FF
|
|
LDY #$27
|
|
@6 STY ZPCE
|
|
STX ZPD1
|
|
LDA COL_TAB+$20,X
|
|
STA ZPD0
|
|
LDA COL_TAB+$27,X
|
|
STA ZPCF
|
|
RTS
|
|
|
|
L0F02 SEC
|
|
LDA ZPF5
|
|
SBC ZPF0
|
|
PHA
|
|
LDA ZPF6
|
|
SBC ZPF1
|
|
STA ZPD9
|
|
BCS @1
|
|
PLA
|
|
EOR #$FF
|
|
ADC #$01
|
|
PHA
|
|
LDA #$00
|
|
SBC ZPD9
|
|
@1 STA ZPDE
|
|
PLA
|
|
STA ZPDD
|
|
SEC
|
|
LDA ZPF7
|
|
SBC ZPF2
|
|
BCS @2
|
|
EOR #$FF
|
|
ADC #$01
|
|
@2 STA ZPDB
|
|
ROR ZPD9
|
|
LDY ZPCE
|
|
LDX ZPDE
|
|
BNE @3
|
|
CMP ZPDD
|
|
BCS @7
|
|
@3 STX ZPE2
|
|
TXA
|
|
LSR A
|
|
STA ZPE4
|
|
LDA ZPDD
|
|
BNE @4
|
|
DEC ZPE2
|
|
@4 STA ZPE1
|
|
ROR A
|
|
STA ZPE3
|
|
@5 LDA ZPE3
|
|
SEC
|
|
SBC ZPDB
|
|
STA ZPE3
|
|
BCS @6
|
|
DEC ZPE4
|
|
BPL @6
|
|
ADC ZPDD
|
|
STA ZPE3
|
|
LDA ZPE4
|
|
ADC ZPDE
|
|
STA ZPE4
|
|
LDA ZPD9
|
|
JSR L0DD8
|
|
@6 BIT ZPD9
|
|
JSR L0E48
|
|
JSR L0FAA
|
|
DEC ZPE1
|
|
BNE @5
|
|
DEC ZPE2
|
|
BPL @5
|
|
RTS
|
|
|
|
@7 STA ZPE1
|
|
TAX
|
|
BEQ @10
|
|
LSR A
|
|
STA ZPE4
|
|
@8 LDA ZPE4
|
|
SEC
|
|
SBC ZPDD
|
|
STA ZPE4
|
|
BCS @9
|
|
ADC ZPDB
|
|
STA ZPE4
|
|
BIT ZPD9
|
|
JSR L0E48
|
|
@9 LDA ZPD9
|
|
JSR L0DD8
|
|
JSR L0FAA
|
|
DEC ZPE1
|
|
BNE @8
|
|
@10 RTS
|
|
|
|
L0F9D LDA ZPF2 ;JSR, JMP from LINETO
|
|
JSR CALCBASE ;calc base addr
|
|
LDA ZPF0
|
|
LDY ZPF1
|
|
JSR CALCBYTE ;calc byte offset
|
|
TAY
|
|
|
|
L0FAA BIT ZPD7
|
|
LDX ZPD5
|
|
DEX
|
|
BEQ @5
|
|
LDA L01E6
|
|
ASL A
|
|
LDA PN_COL
|
|
BCC @1
|
|
LDA F_COL
|
|
@1 CPX #$02
|
|
BNE @2
|
|
JMP L1054
|
|
|
|
@2 BVC @3
|
|
JSR L1199
|
|
@3 CMP #$00
|
|
BEQ @4
|
|
LDA ZPCF
|
|
@4 JMP L1081
|
|
|
|
@5 BIT ZPE7
|
|
BPL @6
|
|
CPY ZPE5
|
|
BEQ @8
|
|
@6 LDA F_COL
|
|
STA ZPDF
|
|
LDA PN_COL
|
|
STA ZPE0
|
|
BIT ZPD7
|
|
BVC @7
|
|
LDA L01E6
|
|
PHA
|
|
LDA #$F0
|
|
STA L01E6
|
|
SEC
|
|
JSR L11AB
|
|
STA ZPDF
|
|
LDA #$00
|
|
STA L01E6
|
|
CLC
|
|
JSR L11AB
|
|
STA ZPE0
|
|
PLA
|
|
STA L01E6
|
|
@7 LDA ZPE0
|
|
ASL A
|
|
ASL A
|
|
ASL A
|
|
ASL A
|
|
ORA ZPDF
|
|
STA L01E6+1
|
|
@8 LDX ZPCF
|
|
LDA L01E6
|
|
ASL A
|
|
LDA #$F0
|
|
BCC @9
|
|
LDA #$0F
|
|
@9 STA ZPCF
|
|
AND L01E6+1
|
|
JSR L10A8
|
|
BIT L01E8
|
|
BPL @11
|
|
LDA L01E6
|
|
ASL A
|
|
LDA #$0F
|
|
BCC @10
|
|
LDA #$F0
|
|
@10 STA ZPCF
|
|
LDA ZPCF
|
|
AND L01E6+1
|
|
JSR L10A8
|
|
@11 STX ZPCF
|
|
LDA (ZPCA),Y
|
|
ORA ZPCF
|
|
LDX L01E6
|
|
BEQ @12
|
|
EOR ZPCF
|
|
@12 STA (ZPCA),Y
|
|
LDA #$F0
|
|
STA ZPE7
|
|
STY ZPE5
|
|
RTS
|
|
|
|
L1054 BVC @1
|
|
JSR L11B7
|
|
@1 JSR L1148
|
|
TAX
|
|
LDA ZPCF
|
|
BEQ @2
|
|
LDA ZPDF
|
|
JSR L1085
|
|
@2 LDA ZPCF
|
|
PHA
|
|
LDA ZPD0
|
|
BEQ @4
|
|
STA ZPCF
|
|
CMP #$60
|
|
PHP
|
|
BNE @3
|
|
DEY
|
|
@3 TXA
|
|
JSR L10A8
|
|
PLP
|
|
BNE @4
|
|
INY
|
|
@4 PLA
|
|
STA ZPCF
|
|
RTS
|
|
|
|
L1081 BIT ZPD2
|
|
BMI L10A8
|
|
|
|
L1085 BIT ZPD7
|
|
BPL @1
|
|
EOR ZPCF
|
|
@1 BIT ZPD6
|
|
BMI @5
|
|
BVS @4
|
|
EOR (ZPCA),Y
|
|
AND ZPCF
|
|
@2 EOR (ZPCA),Y
|
|
@3 STA (ZPCA),Y
|
|
RTS
|
|
|
|
@4 ORA (ZPCA),Y
|
|
BVS @3
|
|
@5 BVC @2
|
|
EOR #$FF
|
|
EOR ZPCF
|
|
AND (ZPCA),Y
|
|
BVS @3
|
|
|
|
L10A8 BIT ZPD7
|
|
BPL @1
|
|
EOR ZPCF
|
|
@1 BIT ZPD6
|
|
BMI @5
|
|
BVS @4
|
|
EOR (ZPCC),Y
|
|
AND ZPCF
|
|
@2 EOR (ZPCC),Y
|
|
@3 STA (ZPCC),Y
|
|
RTS
|
|
|
|
@4 ORA (ZPCC),Y
|
|
BVS @3
|
|
@5 BVC @2
|
|
EOR #$FF
|
|
EOR ZPCF
|
|
AND (ZPCC),Y
|
|
BVS @3
|
|
|
|
L10CB LDY ZPCE ;read color at pen position
|
|
LDX ZPD5
|
|
CPX #$03
|
|
BEQ L10F6
|
|
LDA ZPCF
|
|
BIT ZPD2
|
|
BMI @1
|
|
AND (ZPCA),Y
|
|
BCC @2
|
|
@1 AND (ZPCC),Y
|
|
@2 BEQ @3
|
|
LDA #$0F
|
|
@3 CPX #$01
|
|
BEQ @4
|
|
RTS
|
|
|
|
@4 TAX
|
|
LDA (ZPCC),Y
|
|
CPX #$00
|
|
BEQ @5
|
|
LSR A
|
|
LSR A
|
|
LSR A
|
|
LSR A
|
|
@5 AND #$0F
|
|
RTS
|
|
|
|
L10F6 LDA (ZPCA),Y
|
|
AND ZPCF
|
|
STA ZPDF
|
|
LDA ZPD0
|
|
CMP #$60
|
|
PHP
|
|
BNE @1
|
|
DEY
|
|
@1 AND (ZPCC),Y
|
|
PLP
|
|
BNE @2
|
|
INY
|
|
@2 LDX ZPD1
|
|
INX
|
|
BNE @3
|
|
LSR A
|
|
LSR A
|
|
LSR A
|
|
RTS
|
|
|
|
@3 INX
|
|
BNE @4
|
|
ROL ZPDF
|
|
ROL ZPDF
|
|
ROL A
|
|
RTS
|
|
|
|
@4 INX
|
|
BNE @5
|
|
LDA ZPDF
|
|
LSR A
|
|
LSR A
|
|
RTS
|
|
|
|
@5 INX
|
|
BNE @6
|
|
ROL A
|
|
ROL A
|
|
ROL ZPDF
|
|
ROL A
|
|
ROL ZPDF
|
|
LDA ZPDF
|
|
RTS
|
|
|
|
@6 INX
|
|
BNE @7
|
|
LSR A
|
|
RTS
|
|
|
|
@7 INX
|
|
BNE @8
|
|
ASL ZPDF
|
|
ASL ZPDF
|
|
ROL A
|
|
ASL ZPDF
|
|
ROL A
|
|
ASL ZPDF
|
|
ROL A
|
|
RTS
|
|
|
|
@8 LDA ZPDF
|
|
RTS
|
|
|
|
L1148 LDX ZPD1
|
|
INX
|
|
BNE @1
|
|
STX ZPDF
|
|
ASL A
|
|
ASL A
|
|
ASL A
|
|
RTS
|
|
|
|
@1 INX
|
|
BNE @2
|
|
LSR A
|
|
TAX
|
|
LDA #$00
|
|
ROR A
|
|
ROR A
|
|
STA ZPDF
|
|
TXA
|
|
RTS
|
|
|
|
@2 INX
|
|
BNE @3
|
|
ASL A
|
|
ASL A
|
|
STA ZPDF
|
|
TXA
|
|
RTS
|
|
|
|
@3 INX
|
|
BNE @4
|
|
STX ZPDF
|
|
LSR A
|
|
ROR ZPDF
|
|
LSR A
|
|
ROR ZPDF
|
|
LSR ZPDF
|
|
TAX
|
|
LDA ZPDF
|
|
STX ZPDF
|
|
RTS
|
|
|
|
@4 INX
|
|
BNE @5
|
|
ASL A
|
|
STX ZPDF
|
|
RTS
|
|
|
|
@5 INX
|
|
BNE @6
|
|
STX ZPDF
|
|
LSR A
|
|
ROR ZPDF
|
|
LSR A
|
|
ROR ZPDF
|
|
LSR A
|
|
ROR ZPDF
|
|
LSR ZPDF
|
|
RTS
|
|
|
|
@6 STA ZPDF
|
|
LDA #$00
|
|
RTS
|
|
|
|
L1199 LDA ZPCF
|
|
BIT ZPD2
|
|
BMI @1
|
|
AND (ZPCA),Y
|
|
BPL @2
|
|
@1 AND (ZPCC),Y
|
|
@2 BEQ L11BA
|
|
LDA #$0F
|
|
BNE L11BA
|
|
L11AB LDA (ZPCC),Y
|
|
BCS @1
|
|
LSR A
|
|
LSR A
|
|
LSR A
|
|
LSR A
|
|
@1 AND #$0F
|
|
BPL L11BA
|
|
L11B7 JSR L10F6
|
|
L11BA STA ZPDC
|
|
LDA L01E6
|
|
BPL @1
|
|
LDA F_COL
|
|
JMP @2
|
|
|
|
@1 LDA PN_COL
|
|
@2 ASL A
|
|
ASL A
|
|
ASL A
|
|
LSR ZPDC
|
|
ORA ZPDC
|
|
TAX
|
|
LDA COL_TAB,X
|
|
BCS @3
|
|
LSR A
|
|
LSR A
|
|
LSR A
|
|
LSR A
|
|
@3 AND #$0F
|
|
RTS
|
|
|
|
.endproc
|