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bloxap.a65
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bloxap.a65
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;
;
;
; BloXap
; Version V01.01
; Copyright (C) 2003
; by Christopher A. Mosher
;
;
;
CMAP " ",160,161,162,163,164,165,166,167,168,169,170,171,172,173,174,175,176,177,178,179,180,181,182,183,184,185,186,187,188,189,190,191
CMAP "@",192,193,194,195,196,197,198,199,200,201,202,203,204,205,206,207,208,209,210,211,212,213,214,215,216,217,218,219,220,221,222,223
CMAP "`",224,225,226,227,228,229,230,231,232,233,234,235,236,237,238,239,240,241,242,243,244,245,246,247,248,249,250,251,252,253,254,255
DBUFRADDR = $0900
; page $00 locations
ADTOP = $F8
BAS = $FA ; base address register for printing ($FA-$FB)
CURBAS = $FC ; register for current base address ($FC-$FD)
ADDR = $FE ; address register ($FE-$FF)
; page $03 locations
RESETV = $03F2
RESETEOR = $A5
; ProDOS global page
MLI = $BF00 ; machine language interface entry point
QUIT = $65
READ_BLOCK = $80
WRITE_BLOCK = $81
ERRNODEV = $28
ERRWP = $2B
BITMAP = $BF58
MACHID = $BF98
IBAKVER = $BFFC
IVERSION = $BFFD
KBAKVER = $00
KVERSION = $04
; page $C0 locations
READKBD = $C000
CLEARKBD = $C010
PAGE2? = $C01C
PAGE1 = $C054
PAGE2 = $C055
ETYENTRY = $C300
; global table
ORG $2000 ; starting address $2000
BLOXAP JMP INIT ; BloXap entry point
CMDTBL ; command table (hex values come first)
DB "0123456789ABCDEF"
DB "IKJL"
DB $8B,$8A,$88,$95 ; arrows
DB "UORWTS=-+_.,><H?"
DB $9B ; <esc>
DB $00
JMPTBL ; address table for command routines
DW HEX,HEX,HEX,HEX,HEX,HEX,HEX,HEX
DW HEX,HEX,HEX,HEX,HEX,HEX,HEX,HEX
DW UP,DOWN,LEFT,RIGHT,UP,DOWN,LEFT,RIGHT
DW BEGINBLOC,ENDBLOC
DW READ,WRITE,TEXT,SLOT
DW INCBLOCK,DECBLOCK,INCBLOCK,DECBLOCK
DW INCBLOCK,DECBLOCK,INCBLOCK,DECBLOCK
DW HELP,SCAN
DW EXIT
PAGETBL ; table of pages to allocate to BloXap
DB $20,$21,$22,$23,$24,$25,$26,$27,$28,$29,$2A,$2B,$2C,$2D,$2E,$2F,$30,$31,$32
DB 0
; disassembly tables (ROM)
MNEML DB $1C,$8A,$1C,$23,$5D,$8B,$1B,$A1,$9D,$8A,$1D,$23,$9D,$8B,$1D,$A1
DB $1C,$29,$19,$AE,$69,$A8,$19,$23,$24,$53,$1B,$23,$24,$53,$19,$A1
DB $AD,$1A,$5B,$5B,$A5,$69,$24,$24,$AE,$AE,$A8,$AD,$29,$8A,$7C,$8B
DB $15,$9C,$6D,$9C,$A5,$69,$29,$53,$84,$13,$34,$11,$A5,$69,$23,$A0
MNEMR DB $D8,$62,$5A,$48,$26,$62,$94,$88,$54,$44,$C8,$54,$68,$44,$E8,$94
DB $C4,$B4,$08,$84,$74,$B4,$28,$6E,$74,$F4,$CC,$4A,$72,$F2,$A4,$8A
DB $06,$AA,$A2,$A2,$74,$74,$74,$72,$44,$68,$B2,$32,$B2,$72,$22,$72
DB $1A,$1A,$26,$26,$72,$72,$88,$C8,$C4,$CA,$26,$48,$44,$44,$A2,$C8
FMT1 DB $0F,$22,$FF,$33,$CB,$62,$FF,$73,$03,$22,$FF,$33,$CB,$66,$FF,$77
DB $0F,$20,$FF,$33,$CB,$60,$FF,$70,$0F,$22,$FF,$39,$CB,$66,$FF,$7D
DB $0B,$22,$FF,$33,$CB,$A6,$FF,$73,$11,$22,$FF,$33,$CB,$A6,$FF,$87
DB $01,$22,$FF,$33,$CB,$60,$FF,$70,$01,$22,$FF,$33,$CB,$60,$FF,$70
DB $24,$31,$65,$78
FMT2 DB $00,$21,$81,$82,$59,$4D,$91,$92,$86,$4A,$85,$9D,$49,$5A
CHAR2 DB $D9,$00,$D8,$A4,$A4,$00
CHAR1 DB $AC,$A9,$AC,$A3,$A8,$A4
OPTBL DB $12,$14,$1A,$1C,$32,$34,$3A,$3C,$52,$5A,$64,$72,$74,$7A,$7C,$89
DB $92,$9C,$9E,$B2,$D2,$F2,$FC
DB $00,$00,$00 ; for alignment
DB $8A,$8B,$A5,$AC,$00 ; for MNEML
INDEX DB $38,$FB,$37,$FB,$39,$21,$36,$21,$3A,$F8,$FA,$3B,$FA,$F9,$22,$21
DB $3C,$FA,$FA,$3D,$3E,$3F,$FC,$00
COPYRIGHT ; for alignment (must be $22 (34) bytes)
DB 'Copyright (C) 1989 '
DB 'by Chris Mosher'
; ERR *-COPYRIGHT-34
DB $74,$74,$76,$C6,$00 ; for MNEMR
; variables
ASTO DB $00 ; storage register
CURY DB $00 ; HTAB for cursor
VTAB DB $00 ; line number for printing
INVMASK DB $FF ; inverse AND mask
BYTES DS $10 ; storage for bytes to be printed
MAINLOOP ; the main loop of BloXap
JSR CUROUT ; output the cursor
JSR DSPHELP ; display the help command indicator
JSR DSPINS ; display the block of instructions
JSR FETCH ; fetch a keypress
JSR EXECUTE ; execute a command
BRA MAINLOOP ; repeat
PARMLIST ; parameter list for MLI calls
DB $03 ; 3 parameters
UNIT DB $60 ; current unit number:
; dsss0000 where
; d = drive (0,1)
; sss = slot (1-7)
DBUFR DW DBUFRADDR ; address of data buffer
BLOCK DW $0000 ; current block
INIT ; initialize
LDX #$FF
TXS
LDA #LO $FF69
STA RESETV
LDA #HI $FF69
STA RESETV+1
EOR #RESETEOR
STA RESETV+2
LDA #KBAKVER
STA IBAKVER
LDA #KVERSION
STA IVERSION
JSR ALLOCBX
JSR SET80
JSR DSPTITLE
JSR TLHOME
JSR DSPOFS
JSR ZEROBUFR
LDA #LO DBUFRADDR
STA CURBAS
LDA #HI DBUFRADDR
STA CURBAS+1
JSR PRPAGE
JSR DSPINS
JSR DSPSTMES
LDA #0
STA CURY
LDA #4
STA VTAB
JMP MAINLOOP
WARMUP ; warm up routine (do not start)
; i: none
; o: BloXap ready for
; JMP MAINLOOP
; VTAB preserved
LDA VTAB
PHA
JSR TLHOME
JSR DSPOFS
PLA
PHA
STA VTAB
JSR RDSK1 ; PRPAGE calculating CURBAS with VTAB
JSR DSPINS
JSR DSPSTMES
PLA
STA VTAB
RTS
ALLOCBX ; allocate BloXap program in system memory map
; i: PAGETBL
; o: BITMAP marked appropriately
LDX #0
ABLP1 LDA PAGETBL,X
BEQ EXAB
PHX
PHA ; abcdefgh
AND #$07 ; 00000fgh
TAY
LDX BITMASK,Y ; get proper bit set in X
PLA ; abcdefgh
LSR A
LSR A
LSR A ; 000abcde
TAY
TXA
ORA BITMAP,Y
STA BITMAP,Y
PLX
INX
BNE ABLP1
BITMASK DB $80,$40,$20,$10,$08,$04,$02,$01
EXAB RTS
SET80 ; set eighty column screen
; i: none
; o: 80 column display enabled
LDA MACHID
AND #%00000010 ; 80-column card
BNE S8SK1
JMP EXIT
S8SK1 LDA #$92
JMP ETYENTRY
ZEROBUFR ; zero block buffer
; i: none
; o: data buffer zeroed
LDX #0
ZBLP STZ DBUFRADDR,X
INX
BNE ZBLP
ZBLP2 STZ DBUFRADDR+$0100,X
INX
BNE ZBLP2
STZ DBUFRADDR+$0200,X
STZ DBUFRADDR+$0201,X
RTS
PRPAGE ; print a full screen of bytes ($0100)
; i: CURBAS: starting address
; o: the printed page
; ADDR destroyed
; VTAB destroyed
LDA #4
STA VTAB
LDA CURBAS
STA ADDR
LDA CURBAS+1
STA ADDR+1
PRPLP1 JSR PRLINE
CLC
LDA ADDR
ADC #$10
STA ADDR
LDA ADDR+1
ADC #0
STA ADDR+1
INC VTAB
LDA VTAB
CMP #20
BNE PRPLP1
RTS
PRLINE ; print a line of bytes
; input : ADDR: address to start at (lo hi)
; VTAB: line number (0 org)
; o: line is printed
LDY #0
JSR BASCALC ; use VTAB to calculate BAS
LDA ADDR+1
STA PRLLDA1+2
STA PRLLDA2+2
SEC
SBC #HI DBUFRADDR
JSR AOUT
LDA ADDR
STA PRLLDA1+1
STA PRLLDA2+1
JSR AOUT
LDA #":"|0x80
JSR COUT
LDX #0 ; output byte values
PRLLDA1 LDA $FFFF,X
JSR AOUT
TXA
LSR A
BCC PRLSK1
LSR A
BCC PRLSK1
LDA #$A0
JSR COUT
PRLSK1 INX
CPX #$10
BNE PRLLDA1
LDA #$A0 ; print two spaces
JSR COUT
LDA #$A0
JSR COUT
LDX #0 ; output characters
PRLLDA2 LDA $FFFF,X
JSR COUT
INX
CPX #$10
BNE PRLLDA2
RTS
DSPTITLE ; display title
; i: none
; o: title displayed
; VTAB destroyed
LDA #0
STA VTAB
JSR BASCALC
LDY #0
LDA #$7F
STA INVMASK
JSR PRMESS
DB " "
DB "B l o X a p"
DB " "
DB 0
LDA #$FF
STA INVMASK
RTS
DSPOFS ; display offset addresses at top of page
; i: none
; o: hex numbers printed
; VTAB destroyed
LDA #3
STA VTAB
JSR BASCALC
LDY #5
JSR PRMESS
DB "00010203 04050607 08090A0B 0C0D0E0F"
DB " "
DB "0123456789ABCDEF"
DB 0
RTS
DSPSTMES ; display status messages
; i: none
; o: messages displayed
LDA #21
STA VTAB
JSR BASCALC
LDY #0
JSR PRMESS
DB "slot/drive: /"
DB 0
LDY #12
LDA UNIT ; dsss0000 .
ASL A ; sss00000 d
ASL A ; ss000000 s
ROL A ; s000000s s
ROL A ; 000000ss s
ROL A ; 00000sss 0
ORA #$B0 ; 10110sss (ASCII)
JSR COUT
INY
LDA UNIT ; dsss0000
BMI DSSK1
LDA #$B1 ; 10110001 (ASCII) d = 0 (drive 1)
BNE DSSK2
DSSK1 LDA #$B2 ; 10110010 (ASCII) d = 1 (drive 2)
DSSK2 JSR COUT
INC VTAB
JSR BASCALC
LDY #5
JSR PRMESS
DB "block: $"
DB 0
LDY #13
LDA BLOCK+1
JSR AOUT
LDA BLOCK
JSR AOUT
RTS
DSPHELP ; display the "H" help command indicator
; i: none
; o: message printed
; VTAB preserved
LDA VTAB
PHA
JSR CLRHELP
LDA #21
STA VTAB
JSR BASCALC
LDY #43
JSR PRMESS
DB "Press H for help."
DB 0
PLA
STA VTAB
RTS
CLRHELP ; clear help command indicator
; i: none
; o: message cleared
; VTAB preserved
LDA VTAB
PHA
LDA #21
STA VTAB
DHLP2 JSR BASCALC
LDY #43
DHLP1 LDA #$A0
JSR COUT
CPY #80
BNE DHLP1
INC VTAB
LDA VTAB
CMP #24
BNE DHLP2
PLA
STA VTAB
RTS
DSPINS ; display the block of instructions
; i: CURBAS, CURY
; o: instructions displayed
; ADDR, BAS destroyed
; VTAB preserved
LDA VTAB
PHA
CLC
LDA CURBAS
ADC CURY
STA ADDR
LDA CURBAS+1
ADC #0
STA ADDR+1
LDY #62
LDA #4
STA VTAB
PISLP1 JSR BASCALC
JSR PRINS
INC VTAB
LDA ADDR+1
CMP #HI DBUFRADDR+$0200
BEQ PISSK1
LDA VTAB
CMP #20
BNE PISLP1
BEQ EXPIS
PISSK1 JSR CLRINS
EXPIS PLA
STA VTAB
RTS
PRINS ; print one instruction (ROM)
; i: ADDR: address of op code
; BAS : base address
; Y : HTAB (0 org)
; o: one instruction printed
; ADDR: incremented to first byte
; following the instruction
; BAS preserved
; Y preserved
PHY
SEC
LDA ADDR+1 ; print address: "hilo:"
SBC #HI DBUFRADDR
JSR AOUT
LDA ADDR
JSR AOUT
LDA #":"|0x80
JSR COUT
PHY
LDX #0
LDA (ADDR,X) ; get opcode
TAY ; save opcode
LSR A
BCC PISK1
ROR A
BCS PIER
AND #$87 ; 10000111
PISK1 LSR A
TAX
LDA FMT1,X
BCC PISK2
LSR A
LSR A
LSR A
LSR A
PISK2 AND #$0F ; ....1111
BNE PISK3
PIER LDY #$FC
LDA #0
PISK3 TAX
LDA FMT2,X
STA BYTES
AND #$03 ; ......11
STA BYTES+1
STA ASTO
TYA
LDX #$16
PILP1 CMP OPTBL,X
BEQ PISK4
DEX
BPL PILP1
BMI PISK5
PISK4 LDA INDEX,X
LDY #0
PISK5 BEQ PISK6
AND #$8F ; 1...1111
TAX
TYA
LDY #3
CPX #$8A
BEQ PISK7
PILP3 LSR A
BCC PISK7
LSR A
PILP2 LSR A
ORA #$20
DEY
BNE PILP2
INY
PISK7 DEY
BNE PILP3
PISK6 LDX #3
TAY
LDA MNEML,Y
STA BYTES+2
LDA MNEMR,Y
STA BYTES+3
PILP4 LDA #0
LDY #5
PILP5 ASL BYTES+3
ROL BYTES+2
ROL A
DEY
BNE PILP5
ADC #$BF
PLY
JSR COUT
PHY
DEX
BNE PILP4
PLY
INY
PHY
LDX #6
PILP6 CPX #3
BEQ PISK9
PILP7 ASL BYTES
BCC PISK8
PLY
LDA CHAR1-1,X
JSR COUT
LDA CHAR2-1,X
BEQ PISK8A
JSR COUT
PISK8A PHY
PISK8 DEX
BNE PILP6
PLY
JMP PISK13
PILP8 DEC BYTES+1
BMI PILP7
PLY
JSR AOUT
PHY
PISK9 LDY BYTES+1
LDA BYTES
CMP #$E8
LDA (ADDR),Y
BCC PILP8
LDY ADDR+1
TAX
BPL PISK10
DEY
PISK10 ADC ADDR
BCC PISK11
INY
PISK11 TAX
INX
BNE PISK12
INY
PISK12 SEC
TYA
SBC #HI DBUFRADDR
PLY
JSR AOUT
TXA
JSR AOUT
PILP9 LDA #$A0
JSR COUT
PISK13 CPY #80
BNE PILP9
INC ASTO
CLC
LDA ADDR
ADC ASTO
STA ADDR
LDA ADDR+1
ADC #0
STA ADDR+1
PLY
RTS
CLRINS ; clear instruction block (below VTAB)
; i: VTAB: line to clear down from
; o: lines cleared (col. 62-79)
LDA VTAB
CMP #20
BEQ EXCI
JSR BASCALC
LDY #62
CILP1 LDA #$A0
JSR COUT
CPY #80
BNE CILP1
INC VTAB
JMP CLRINS
EXCI RTS
CUROUT ; output cursor
; i: CURBAS: base byte address
; CURY: offset byte in line
; VTAB: line number
; o: inverse cursor printed
; CURBAS, CURY, VTAB preserved
LDA VTAB
PHA
JSR BASCALC ; calculate BAS from VTAB
LDY #0
SEC
LDA CURBAS+1
SBC #HI DBUFRADDR
JSR AINVOUT
LDA CURBAS
JSR AINVOUT
LDA CURY ; calculate Y for AINVOUT (in A) and push
TAY
LSR A
LSR A
STA ASTO
TYA
ASL A
ADC #5
ADC ASTO
PHA
LDA (CURBAS),Y ; get byte and push (first pl/ph Y for AINVOUT)
PLY
PHY
PHA
JSR AINVOUT ; output inverse byte value
CLC ; calculate Y for CINVOUT
LDA #43
ADC CURY
TAY
PLA ; get byte
JSR CINVOUT ; output inverse character
LDA #3
STA VTAB
JSR BASCALC
PLY ; get Y for AINVOUT from before
LDA CURY
JSR AINVOUT
CLC ; calculate Y for NIBOUT
LDA #43
ADC CURY
TAY
LDA #$7F
STA INVMASK
LDA CURY
JSR NIBOUT
LDA #$FF
STA INVMASK
PLA
STA VTAB
RTS
CUROFF ; turn off cursor
; i: CURBAS: base byte address
; CURY: offset byte in line
; VTAB: line number
; o: inverse cursor removed
; CURBAS, CURY, VTAB preserved
LDA VTAB
PHA
JSR BASCALC ; calculate BAS from VTAB
LDY #0
SEC
LDA CURBAS+1
SBC #HI DBUFRADDR
JSR AOUT
LDA CURBAS
JSR AOUT
LDA CURY ; calculate Y for AOUT (in A) and push
TAY
LSR A
LSR A
STA ASTO
TYA
ASL A
ADC #5
ADC ASTO
PHA
LDA (CURBAS),Y ; get byte and push (first pl/ph Y for AOUT)
PLY
PHY
PHA
JSR AOUT ; turn off inverse byte value
CLC ; calculate Y for CINVOUT
LDA #43
ADC CURY
TAY
PLA ; get byte
JSR COUT ; turn off inverse character
LDA #3
STA VTAB
JSR BASCALC
PLY ; get Y for AOUT from before
LDA CURY
JSR AOUT
CLC ; calculate Y for NIBOUT
LDA #43
ADC CURY
TAY
LDA CURY
JSR NIBOUT
PLA
STA VTAB
RTS
SCROLLUP ; scroll monitor window up
; i: none
; o: window is scrolled up
; (bottom line not cleared)
; VTAB := 19
STA PAGE2
SULP1 LDY #29
SULP2 LDA $0680,Y
STA $0600,Y
LDA $0700,Y
STA $0680,Y
LDA $0780,Y
STA $0700,Y
LDA $0428,Y
STA $0780,Y
LDA $04A8,Y
STA $0428,Y
LDA $0528,Y
STA $04A8,Y
LDA $05A8,Y
STA $0528,Y
LDA $0628,Y
STA $05A8,Y
LDA $06A8,Y
STA $0628,Y
LDA $0728,Y
STA $06A8,Y
LDA $07A8,Y
STA $0728,Y
LDA $0450,Y
STA $07A8,Y
LDA $04D0,Y
STA $0450,Y
LDA $0550,Y
STA $04D0,Y
LDA $05D0,Y
STA $0550,Y
DEY
BPL SULP2
LDA PAGE2?
BPL EXSU
STA PAGE1
BMI SULP1
EXSU LDA #19
STA VTAB
RTS
SCROLLDW ; scroll monitor window down
; i: none
; o: window is scrolled down
; (top line not cleared)
; VTAB := 4
STA PAGE2
SDLP1 LDY #29
SDLP2 LDA $0550,Y
STA $05D0,Y
LDA $04D0,Y
STA $0550,Y
LDA $0450,Y
STA $04D0,Y
LDA $07A8,Y
STA $0450,Y
LDA $0728,Y
STA $07A8,Y
LDA $06A8,Y
STA $0728,Y
LDA $0628,Y
STA $06A8,Y
LDA $05A8,Y
STA $0628,Y
LDA $0528,Y
STA $05A8,Y
LDA $04A8,Y
STA $0528,Y
LDA $0428,Y
STA $04A8,Y
LDA $0780,Y
STA $0428,Y
LDA $0700,Y
STA $0780,Y
LDA $0680,Y
STA $0700,Y
LDA $0600,Y
STA $0680,Y
DEY
BPL SDLP2
LDA PAGE2?
BPL EXSD
STA PAGE1
BMI SDLP1
EXSD LDA #4
STA VTAB
RTS
GETBLOCK ; input block number
; i: none
; o: BLOCK
; ProDOS error message cleared
; VTAB destroyed
LDA #22
STA VTAB
JSR BASCALC
LDY #13
LDA BLOCK+1
JSR AINVOUT
GBLP2 JSR FETCH
LDX #$0F
GBLP1 CMP CMDTBL,X
BEQ GBSK2 ; if nibble, branch
DEX
BPL GBLP1
CMP #$8D ; <return>
BNE GBLP2
LDA BLOCK+1
JMP GBSK1
GBSK2 TXA
ASL A
ASL A
ASL A
ASL A
STA ASTO
DEY
DEY
JSR AINVOUT
GBLP4 JSR FETCH
LDX #$0F
GBLP3 CMP CMDTBL,X
BEQ GBSK3
DEX
BPL GBLP3
JMP GBLP4
GBSK3 TXA
ORA ASTO
DEY
DEY
STA BLOCK+1
JSR AOUT
LDA BLOCK
JSR AINVOUT
GBLP6 JSR FETCH
LDX #$0F
GBLP5 CMP CMDTBL,X
BEQ GBSK4 ; if nibble, branch
DEX
BPL GBLP5
JMP GBLP6
GBSK4 TXA
ASL A
ASL A
ASL A
ASL A
STA ASTO
DEY
DEY
JSR AINVOUT
GBLP8 JSR FETCH
LDX #$0F
GBLP7 CMP CMDTBL,X
BEQ GBSK5
DEX
BPL GBLP7
JMP GBLP8
GBSK5 TXA
ORA ASTO
STA BLOCK
GBSK1 DEY
DEY
JSR AOUT
JSR CLRERR
RTS
ERROR ; print ProDOS error message
; i: A: error number
; o: message printed
; VTAB preserved
; ASTO destroyed
STA ASTO
LDA VTAB
PHA
LDA #21
STA VTAB
JSR BASCALC
LDY #19
LDA ASTO
CMP #ERRNODEV