Applecorn/auxmem.chario.s
2021-08-29 01:13:31 -04:00

414 lines
14 KiB
ArmAsm

* AUXMEM.CHARIO.S
* (c) Bobbi 2021 GPLv3
*
* AppleMOS Character I/O
* KERNEL/CHARIO.S
*****************
* Character read and write
*
* 14-Aug-2021 Flashing cursor and INKEY sync'd to frame rate
* with VBLK. Ensured cursor turned on straightaway.
* 15-Aug-2021 Cursor keys move copy cursor, copy reads char.
* Copy cursor not visible yet.
* 16-Aug-2021 Copy cursor and Edit cursor visible.
* 17-Aug-2021 OSBYTE 4 for cursors, OSBYTE 221-228 for topbit
* keys.
* 21-Aug-2021 FIXED: If screen scrolls, copy cursor ends on
* wrong line.
* FIXED: KBDREAD has several paths that don't
* test ESCHAR.
* FIXED: INKEY doesn't restore cursor on timeout.
* The three separate cursors can be set seperately.
* TEMP, move to VDU.S
FLASHER EQU $290
CURSOR EQU $291
CURSORED EQU $292
CURSORCP EQU $293
OLDCHAR EQU $294
COPYCHAR EQU $295
FXTABCHAR EQU BYTEVARBASE+219
FXESCCHAR EQU BYTEVARBASE+220
FXKEYBASE EQU BYTEVARBASE+221
FXESCON EQU BYTEVARBASE+229
FXESCEFFECT EQU BYTEVARBASE+230
FX200VAR EQU BYTEVARBASE+200
FX254VAR EQU BYTEVARBASE+254
FX2VAR EQU BYTEVARBASE+$B1
FX3VAR EQU BYTEVARBASE+$EC
FX4VAR EQU BYTEVARBASE+$ED
* OSWRCH handler
****************
* Send a character to current output
* All registers preserved
*
WRCHHND PHA
PHX
PHY
* TO DO Check any output redirections
* TO DO Check any spool output
JSR OUTCHAR
* TO DO Check any printer output
PLY
PLX
PLA
RTS
* Character Input
*****************
* Default keyboard OSBYTE variables
*DEFBYTELOW EQU 219 ; First default OSBYTE value
*DEFBYTE DB $09,$1B ; Default key codes
* DB $01,$D0,$E0,$F0 ; Default key expansion
* DB $01,$80,$90,$00 ; Default key expansion
*DEFBYTEEND
* TEMP as no *KEY
* Default keyboard OSBYTE variables
DEFBYTELOW EQU 219 ; First default OSBYTE value
DEFBYTE DB $09,$1B ; Default key codes
DB $C0,$D0,$E0,$F0 ; Default key expansion
DB $80,$90,$A0,$B0 ; Default key expansion
DEFBYTEEND
KBDINIT LDX #DEFBYTEEND-DEFBYTE-1
:KBDINITLP LDA DEFBYTE,X ; Initialise KBD OSBYTE variables
STA BYTEVARBASE+DEFBYTELOW,X
DEX
BPL :KBDINITLP
LDA #$C0
STA FX254VAR ; Also returns default MODE=0
RTS
* OSRDCH/INKEY handler
**********************
* Read a character from current input
* All registers preserved except A, Carry
* Flashes a fake cursor while waiting for input
*
RDCHHND LDA #$80 ; flag=wait forever
PHY
TAY
BRA INKEYGO ; Wait forever for input
* XY<$8000 - wait for a keypress
INKEY PHY ; Dummy PHY to balance RDCH
INKEYGO PHX ; Save registers
PHY
*
BIT VDUSTATUS ; Enable editing cursor
BVC INKEYGO2 ; No editing cursor
JSR GETCHRC ; Get character under cursor
STA COPYCHAR ; Save char under edit cursor
LDA CURSORED
JSR PUTCHRC ; Display edit cursor
JSR COPYSWAP1 ; Swap to copy cursor
INKEYGO2 JSR GETCHRC ; Get character under cursor
STA OLDCHAR
*
CLI
BRA INKEY1 ; Turn cursor on
*
INKEYLP1 PHX
INKEYLP2 PHY
INKEYLP CLC
LDA #$01 ; Slow flash, every 32 frames
BIT VDUSTATUS
BVC INKEY0
ASL A ; Fast flash, every 16 frames
INKEY0 ADC FLASHER
STA FLASHER
AND #15
BNE INKEY3 ; Not time to toggle yet
LDA OLDCHAR ; Prepare to remove cursor
BIT FLASHER
BMI INKEY2 ; Remove cursor
INKEY1 LDA CURSOR ; Add cursor
BIT VDUSTATUS
BVC INKEY2
LDA CURSORCP
INKEY2 JSR PUTCHRC ; Toggle cursor
INKEY3 LDA ESCFLAG
BMI INKEYOK ; Escape pending, return it
INKEY4 JSR KEYREAD ; Test for input, all can be trashed
BCC INKEYOK ; Char returned, return it
*
* VBLK pulses at 50Hz, changes at 100Hz
* (60Hz in US, will need tweeking)
LDX $C019 ; Get initial VBLK state
INKEY5 BIT $C000
BMI INKEY4 ; Key pressed
TXA
EOR $C019
BPL INKEY5 ; Wait for VBLK change
*
PLY
BMI INKEYLP2 ; Loop forever
PLX
TXA
BNE INKEYDEC ; Decrement XY
DEY
INKEYDEC DEX
BNE INKEYLP1 ; Not 0, loop back
TYA
BNE INKEYLP1 ; Not 0, loop back
*
PHY
JSR INKEYOFF ; Restore cursors
PLY
*
DEY ; Y=$FF
TYA ; A=$FF
PLX ; Drop dummy PHY
SEC
RTS
* Timeout: CS, AY=$FFFF, becomes XY=$FFFF
INKEYOK PHA
*
JSR INKEYOFF ; Restore cursors
*
* LDA OLDCHAR ; Remove editing cursor
* JSR PUTCHRC ; Remove cursor
* BIT VDUSTATUS
* BVC INKEYOK2 ; No editing cursor
* JSR COPYSWAP1 ; Swap cursor back
* LDA COPYCHAR
* JSR PUTCHRC ; Remove edit cursor
*
INKEYOK2 PLA
PLY ; <$80=INKEY or $80=RDCH
PLX ; Restore X
PLY ; <$80=INKEY or restore=RDCH
PHA ; Save char for a mo
LDA ESCFLAG
ASL A ; Cy=Escape flag
PLA ; Get char back
RTS
* Character read: CC, A=char, X=???, Y<$80
* Escape: CS, A=?? , X=???, Y<$80
INKEYOFF LDA OLDCHAR ; Remove editing cursor
BIT VDUSTATUS
BVC INKEYOFF2 ; No editing cursor
JSR PUTCHRC ; Remove cursor
JSR COPYSWAP1 ; Swap cursor back
LDA COPYCHAR ; Remove edit cursor
INKEYOFF2 JMP PUTCHRC
BYTE81 TYA
BMI NEGINKEY ; XY<0, scan for keypress
JSR INKEY ; XY>=0, wait for keypress
* Y=$FF, A=FF, X=??, CS - timeout
* Y<$80, A=esc, X=??, CS - escape
* Y<$80, A=char, X=??, CC - character read
TAX ; X=character returned
TYA
BMI BYTE81DONE ; Y=$FF, timeout
LDY #$00
BCC BYTE81DONE ; CC, not Escape
LDY #$1B ; Y=27
BYTE81DONE RTS
* Returns: Y=$FF, X=$FF, CS - timeout
* Y=$1B, X=???, CS - escape
* Y=$00, X=char, CC - keypress
NEGINKEY CPX #$01
LDX #$00 ; Unimplemented
LDY #$00
BCS NEGINKEY0
LDX #$2E ; INKEY-256 = $2E = Apple IIe
NEGINKEY0 CLC
RTS
* KERNEL/KEYBOARD.S
*******************
* KEYREAD
************************
* Test for and read from input,
* expanding keyboard special keys
*
* On exit, CS=no keypress
* CC=keypress
* A =keycode, X,Y=corrupted
KEYREAD
* TO DO: check *EXEC source
* LDY FXVAREXEC
* BEQ KEYREAD1
* JSR OSBGET
* BCC KEYREADOK
* LDA #0
* STA FXVAREXEC
* JSR OSFIND
* KEYREAD1
*
* TO DO: expand current soft key
* LDA SOFTKEYLEN
* BEQ KEYREAD2
* LDX SOFTKEYOFF
* LDA SOFTKEYS,X
* INC SOFTKEYOFF
* DEC SOFTKEYLEN
* CLC
* RTS
* KEYREAD2
*
JSR KBDREAD ; Fetch character from KBD "buffer"
BCS KEYREADOK ; Nothing pending
*
TAY
BPL KEYREADOK ; Not top-bit key
AND #$CF
CMP #$C9
BCC KEYSOFT ; Not cursor key
LDX FX4VAR
BEQ KEYCURSOR ; *FX4,0 - editing keys
DEX
BNE KEYSOFT1 ; Not *FX4,1 - soft key
LDY FXTABCHAR
CMP #$C9
BEQ KEYREADOKY ; TAB key
SBC #$44 ; Return $88-$8B
TAY
KEYREADOKY TYA
KEYREADOK1 CLC
KEYREADOK RTS
*
* Process soft key
KEYSOFT1 LDX FX254VAR
CPX #$C0
BCC KEYSOFT
AND #$BF
TAY
KEYSOFT TYA
LSR A
LSR A
LSR A
LSR A ; A=key DIV 16
EOR #$04 ; Offset into KEYBASE
TAX
LDA FXKEYBASE-8,X
* TO DO:
*BEQ KEYNONE ; $00=ignored
*DEC A
*BEQ expandfunction
CMP #2 ; *TEMP*
BCC KEYNONE ; *TEMP*
TYA
AND #$0F
CLC
ADC FXKEYBASE-8,X
CLC
RTS
* Process cursor keys
KEYCURSOR CMP #$C9
BEQ KEYCOPY
PHA
LDA OLDCHAR
JSR PUTCHRC ; Remove cursor
PLA
JSR COPYMOVE ; Move copy cursor
JSR GETCHRC ; Save char under cursor
STA OLDCHAR
KEYNONE SEC
RTS
KEYCOPY LDA FXTABCHAR ; Prepare TAB if no copy cursor
BIT VDUSTATUS
BVC KEYREADOK1 ; No copy cursor, return TAB
LDA OLDCHAR ; Get the char under cursor
PHA
JSR OUTCHARGO ; Output it to restore and move cursor
JSR GETCHRC ; Save char under cursor
STA OLDCHAR
PLA
BNE KEYREADOK1 ; Ok character
SEC
JMP BEEP ; Beep and return CS=No char
* KBDREAD
************************
* Test for and fetch key from keyboard
*
* On exit, CS=no keypress
* CC=keypress
* A =keycode, X=corrupted
* Apple+Letter -> Ctrl+Letter
* Apple+Digits -> 80+x, 90+x, A0+x
* TAB -> $C9
* Cursors -> $CC-$CF
*
KBDREAD CLV ; VC=return keypress
KBDTEST LDA $C000 ; VS here to test for keypress
EOR #$80 ; Toggle bit 7
CMP #$80
BCS KBDDONE ; No key pressed
BVS KBDDONE ; VS=test for keypress
STA $C010 ; Ack. keypress
BIT $C061
BMI KBDLALT ; Left Apple pressed
BIT $C062
BMI KBDRALT ; Right Apple pressed
CMP #$09
BEQ KBDTAB ; TAB is dual action TAB/COPY
CMP #$08
BCC KBDCHKESC ; <$08 not cursor key
CMP #$0C
BCC KBDCURSR ; $08-$0B are cursor keys
CMP #$15
BNE KBDCHKESC ; $15 is cursor key
*
KBDCUR15 LDA #$0D ; Convert RGT to $09
KBDTAB SBC #$04 ; Convert TAB to &C9
KBDCURSR CLC
ADC #$C4 ; Cursor keys $C0+x
BRA KBDCHKESC
KBDRALT ; Right Apple key pressed
KBDLALT CMP #$40 ; Left Apple key pressed
BCS KBDCTRL
CMP #$30
BCC KBDCHKESC ; <'0'
CMP #$3A
BCS KBDCHKESC ; >'9'
KBDFUNC AND #$0F ; Convert Apple-Num to function key
ORA #$80
BIT $C062
BPL KBDCHKESC ; Left+Digit -> $8x
ORA #$90 ; Right+Digit -> $9x
BIT $C061
BPL KBDCHKESC
EOR #$30 ; Left+Right+Digit -> $Ax
BRA KBDCHKESC
KBDCTRL AND #$1F ; Apple-Letter -> Ctrl-Letter
*
* Test for Escape key
KBDCHKESC TAX ; X=keycode
EOR FXESCCHAR ; Current ESCAPE char?
ORA FXESCON ; Is ESCAPE an ASCII char?
BNE KBDNOESC ; Not ESCAPE or ESCAPE=ASCII
LDA FX200VAR ; Is ESCAPE ignored?
LSR A ; Check bit 0
BCS KBDDONE ; ESCAPE completely ignored
SEC
ROR ESCFLAG ; Set Escape flag
KBDNOESC TXA ; A=keycode
CLC ; CLC=Ok
KBDDONE RTS