Applecorn/auxmem.chario.s
2022-09-20 23:29:07 -04:00

443 lines
16 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.
* 02-Sep-2021 INKEY-256 tests Apple IIe vs IIc.
* 05-Sep-2021 KBDINIT returns startup value to pass to VDUINT.
* 09-Sep-2021 Moved keyboard OSBYTEs to here.
* 12-Sep-2021 COPY calls new VDU entry point.
* 15-Sep-2021 INKEY(0) tests once and returns immediately.
* 30-Nov-2021 With *FX4,<>0 TAB returns $09, allows eg VIEW to work.
* 13-Sep-2022 Fix bug in INKEY with misbalanced stack when Escape pressed
* TO DO: CHKESC should go through translations before testing.
FLASHER EQU BYTEVARBASE+176 ; VSync counter for flashing cursor
FXEXEC EQU BYTEVARBASE+198
FXSPOOL EQU BYTEVARBASE+199
FXTABCHAR EQU BYTEVARBASE+219
FXESCCHAR EQU BYTEVARBASE+220
FXKEYBASE EQU BYTEVARBASE+221
FXESCON EQU BYTEVARBASE+229
FXESCEFFECT EQU BYTEVARBASE+230
FX200VAR EQU BYTEVARBASE+200
FX254VAR EQU BYTEVARBASE+254
FX2VAR EQU BYTEVARBASE+$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
PHA
JSR OUTCHAR
* TO DO Check any printer output
* BCC WRCHHND3
* PLA
* PHA
* JSR PRNCHAR
* WRCHHND3
* TO DO Check any spool output
LDY FXSPOOL
BEQ WRCHHND4
PLA
PHA
JSR OSBPUT
WRCHHND4 PLA
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,$B0 ; Default key expansion
DEFBYTEEND
KBDINIT LDX #DEFBYTEEND-DEFBYTE-1
:KBDINITLP LDA DEFBYTE,X ; Initialise KBD OSBYTE variables
STA BYTEVARBASE+DEFBYTELOW,X
DEX
BPL :KBDINITLP
LDX #$C0
STX FX254VAR ; b7-b4=default KBD map, b3-b0=default MODE
BIT SETV
JSR KBDTEST
BCS :KBDINITOK ; Return default MODE=0
STA $C010 ; Ack. keypress
TAX ; Use keypress as default MODE
:KBDINITOK TXA
RTS
* OSRDCH/INKEY handler
**********************
* Read a character from current input
* All registers preserved except A, Carry
* Flashes a soft 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
BRA INKEY1 ; Turn cursor on
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
PLY
BCC INKEYOK ; Char returned, return it
BMI INKEY6 ; Loop forever, skip countdown
PLX
BNE INKEY5
TYA
BEQ INKEYOUT ; XY=0, timed out
DEY ; 16-bit decrement
INKEY5 DEX
PHX
INKEY6 PHY
*
* VBLK pulses at 50Hz/60Hz, toggles at 100Hz/120Hz
LDX $C019 ; Get initial VBLK state
INKEY8 BIT $C000
BMI INKEY4 ; Key pressed
TXA
EOR $C019
BPL INKEY8 ; Wait for VBLK change
BMI INKEYLP ; Loop back to key test
INKEYOUT PLA ; Drop stacked Y
LDA #$FF ; Prepare to stack $FF
*
INKEYOK PHA ; Save key or timeout
PHP ; Save CC=key, CS=timeout
LDA OLDCHAR ; Prepare for main cursor
BIT VDUSTATUS
BVC INKEYOFF2 ; No editing cursor
JSR PUTCHRC ; Remove cursor
JSR COPYSWAP1 ; Swap cursor back
LDA COPYCHAR ; Remove main cursor
INKEYOFF2 JSR PUTCHRC ; Remove cursor
*
PLP
BCS INKEYOK3 ; Timeout
LDA ESCFLAG ; Keypress, test for Escape
ASL A ; Cy=Escape flag
PLA ; Get char back
PLX ; Restore X,Y for key pressed
INKEYOK3 PLY ; Or pop TimeOut
RTS
* RDCH Character read: CC, A=char, X=restored, Y=restored
* RDCH Escape: CS, A=char, X=restored, Y=restored
* INKEY Character read: CC, A=char, X=???, Y<$80
* INKEY Escape: CS, A=char, X=???, Y<$80
* INKEY Timeout: CS, A=???, X=???, Y=$FF
BYTE81 TYA
BMI NEGINKEY ; XY<0, scan for keypress
JSR INKEY ; XY>=0, wait for keypress
* Character read: CC, A=char, X=???, Y<$80
* Escape: CS, A=char, X=???, Y<$80
* Timeout: CS, A=???, X=???, Y=$FF
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=???, CS - timeout
* Y=$1B, X=???, CS - escape
* Y=$00, X=char, CC - keypress
NEGINKEY CPX #$01
LDX #$00 ; Unimplemented
BCS NEGINKEY0
JSR NEGCALL ; Read machine ID from aux
TAX ; *TEST*
BIT $E0 ; *TEST*
BVS NEGINKEY1 ; *TEST*
LDX #$2C
TAY
BEQ NEGINKEY0 ; $00 = Apple IIc -> INKEY-256 = $2C
LDX #$2E
AND #$0F
BEQ NEGINKEY0 ; $x0 = Apple IIe -> INKEY-256 = $2E
LDX #$2A ; else = Apple IIgs -> INKEY-256 = $2A
NEGINKEY0 LDY #$00
NEGINKEY1 CLC
RTS
NEGCALL >>> XF2MAIN,MACHRD ; Try to read Machine ID
* KERNEL/KEYBOARD.S
*******************
* KEYREAD
************************
* Test for and read from input,
* expanding keyboard special keys
*
* On exit, CS=no keypress
* CC=keypress
* A =keycode, X,Y=corrupted
KEYREAD LDY FXEXEC ; See if *EXEC file is open
BEQ KEYREAD1
JSR OSBGET ; Read keypress from file
BCC KEYREADOK
LDA #0 ; EOF, close *EXEC file
STA FXEXEC
JSR OSFIND
KEYREAD1
*
* TO DO: expand current soft key
* LDA SOFTKEYLEN
* BEQ KEYREAD2
* LDX SOFTKEYOFF
* LDA SOFTKEYS,X
* INC SOFTKEYOFF
* DEC SOFTKEYLEN
* CLC
* RTS
* KEYREAD2
*
JSR KBDREAD ; Fetch character from KBD "buffer"
BCS KEYREADOK ; Nothing pending
TAY
BPL KEYREADOK ; Not top-bit key
AND #$CF
CMP #$C9
BCC KEYSOFT ; Not cursor key
LDX FX4VAR
BEQ KEYCURSOR ; *FX4,0 - editing keys
LDY FXTABCHAR
CMP #$C9
BEQ KEYREADOKY ; TAB key
DEX
BNE KEYSOFT1 ; Not *FX4,1 - soft 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 OUTCHARCP ; 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
* Process pending Escape state
BYTE7E LDX #$00 ; $7E = ack detection of ESC
BIT ESCFLAG
BPL BYTE7DOK ; No Escape pending
LDA FXESCEFFECT ; Process Escape effects
BEQ BYTE7E2
STA FXLINES ; Clear scroll counter
* JSR STAREXEC0 ; Close any EXEC file
* JSR FLUSHALL ; Flush all buffers
BYTE7E2 LDX #$FF ; X=$FF, Escape was pending
BYTE7C CLC ; &7C = clear escape condition
BYTE7D ROR ESCFLAG ; $7D = set escape condition
BYTE7DOK RTS
BYTE76 LDX #$00 ; Update LEDs and return X=SHIFT
RTS ; Not possible with Apple