**********************************
* MOUSE.CLOCK Source Code        *
* By John R. Vokey               *
* (C) 1991 by MindCraft Publ.    *
**********************************
;
;
*=================================
;             Equates
*=================================
;
*   Set System DOS:
PRODOS EQU $21 PRODOS = $21, DOS = 0
;
*     Monitor:
ACC EQU $45 save A loc on IRQ
SAVEA EQU $FC temp for Acc
SAVEX EQU SAVEA+1 temp for X reg
SAVEY EQU SAVEX+1 temp for Y reg
SCREEN EQU $41D 40-col screen position
USER EQU $0000 User's interrupt handler
;
*     Applesoft:
CHKCOM EQU $DEBE Check for comma at TXTPTR
PTRGET EQU $DFE3 returns variable pointer
VARPNT EQU $83 Applesoft pointer
ERROR EQU $D412 error routine
;
*     Mouse:
MSLOT EQU $C400 assume slot 4
NUM EQU $FF used as a temp
;
*     ProDOS:
ALLOC EQU $40 allocate interrupt code
MLI EQU $BF00 Machine Language Interface
DATETIME EQU $BF06 Date/time jump
PTIME EQU $BF92 time locations
BITMAP EQU $BF58 system bit map
GOSYSTEM EQU $BE70 BASIC.SYSTEM command call
GETBUFR EQU $BEF5 Get Buffer
ERROUT EQU $BE09 error exit
;
*     DOS 3.3:
BUFCNT EQU $AA57 # of buffers to create
BUFPTR EQU $9D00 pointer to new buffer
BUFBLD EQU $A7D4 build buffers
DOSLOC EQU $9C00 relocation page
;
*     Origin:
 ORG $4000-$44-PRODOS
;
*=================================
;            Relocate
*=================================
;
 DO PRODOS
 LDA #1 ask BASIC.SYSTEM for 1 page
 JSR GETBUFR
 BCS BADERR Error
 STA VARPNT+1 (for move)
 PHA  save it
 LSR A shift down
 LSR A
 LSR A
 TAX  use as index into bitmap
 PLA
 EOR #$FF complement
 AND #$7 mask off high bits
 SEC
 TAY
 LDA #0 clear Acc
PLOOP ROL A shift 'Y' times
 DEY
 BPL PLOOP
 ORA BITMAP,X set bit
 STA BITMAP,X flag "used"
 LDA VARPNT+1 recover hbyte
 STA P2
 STA P4+1
;
 ELSE
 LDA #>DOSLOC lbyte of space
 SEC
 SBC #$26 name, pointers, etc.
 STA BUFPTR
 LDA #<DOSLOC hbyte
 SBC #0
 STA BUFPTR+1
 LDA #3 set default (3) buffers
 STA BUFCNT
 JSR BUFBLD create space
 LDA #<DOSLOC
 STA D2+1
 FIN
;
MOVE LDY #0
 STY VARPNT
 STA VARPNT+1
MLOOP LDA SETMOUSE,Y
 STA (VARPNT),Y
 DEY
 BNE MLOOP
;
 LDX RBYTES get # of bytes
 LDA VARPNT+1 recover page #
RLOOP PHA
 LDA RBYTES,X get index of byte to fix
 TAY  use Y as index
 PLA
 STA (VARPNT),Y fix it
 DEX  more?
 BNE RLOOP Yes, loop until done
;
*=================================
;           Initialize
*=================================
;
 DO PRODOS
 JSR MLI call command dispatcher
 DFB ALLOC to install interrupt
 DW PRMLST handler
 BCC DOTIME
BADERR JMP ERROUT exit if error
PRMLST DFB 2,0
 DFB >IHAND
P2 DFB <IHAND
;
 ELSE
*     set DOS interrupts
 LDA #>IHAND
 STA $3FE
D2 LDA #<IHAND
 STA $3FF
 FIN
;
*     Setup ProDOS time call:
DOTIME DO PRODOS
 LDA #$4C a "JMP"
 STA DATETIME
 LDA #>SAVTIME and point to
 STA DATETIME+1 time routine
P4 LDA #<SAVTIME
 STA DATETIME+2
 FIN
;
*=================================
;           Start Clock
*=================================
;
; The mouse will be placed in
; TRANSPARENT mode with the vertical
; blanking signal active such that
; each VBL will result in an interrupt.
; Since VBL occurs once every 1/60 of
; a second, 3 VBLs is equivalent to
; 5 centiseconds.
;
* Permanent code begins here
;
SETMOUSE LDY #$19
M1 JSR CALL do INITMOUSE
 BCS MSEERR if error, exit
 SEI Disable Interrupts
;
SETMODE LDA #$9 set TRANSPARENT mode
SETMDE LDY #$12 (VBLINT active)
M2 JSR CALL do SETMOUSE
 BCS MSEERR if error, exit
 CLI enable interrupts
 RTS  Done
;
MSEERR LDX #$17 make "ERROR"
 JMP ERROR
;
*=================================
;           Kill Mouse
*=================================
;
; Call this routine to turn mouse.clock
; off; call the above routine to start
; it again.
;
KILLMSE SEI turn off interrupts
 LDA #0 mouse off
 BEQ SETMDE do SETMOUSE, exit
;
*=================================
;           Call Mouse
*=================================
;
; Input: A - mode (if any)
;        Y - offset to command call
;          - assumes mouse in MSLOT
; Output: X, Y, A scrambled
;
CALL PHA save mode 
 LDA MSLOT,Y get low byte
R1 STA DOIT+1 self-modifying code
 LDX #<MSLOT X, Y housekeeping
 LDY #<MSLOT-$C000*$10
 PLA recover mode
DOIT JMP MSLOT do mouse call, exit
;
*=================================
;         Interrupt Handler
*=================================
;
IHAND CLD ProDOS wants this
 LDA $45 save regs for old monitors
 STA SAVEA
 STX SAVEX
 STY SAVEY
 LDY #$13 Who interrupted?
R2 JSR CALL do SERVEMOUSE
 BCS EXIT Not mouse, so go
 SEI Mouse, so disable interrupts
;
*=================================
;     Function: TIME$
*=================================
;
; This routine adds a TIME$ function
; to Applesoft BASIC.  On every
; 3 vertical blanks, the time count for
; CSECS, SECS, MINS, and HOUR is updated.
; The time is then converted to its
; ASCII equivalent in a HH:MM:SS CS
; format and stored in OUTSTR.
; If screen display is selected
; (DSPTGL = TRUE), OUTSTR is output
; to the screen at SCREEN.
;
TIMER DEC TIMECNT count 3 cycles
 BNE EXIT If not 0, go
 LDY #3 reset cycle count
T1 STY TIMECNT
 LDA #5 increment msecs
TLOOP ADC TIME,Y increment counter
 CMP TIMLIM,Y counter done?
 STA TIME,Y
 LDA #0
 BCC NXTCNT no, next counter
T2 STA TIME,Y yes, clear it
NXTCNT DEY next counter, please
 BPL TLOOP and go again
;
F1 LDA TIME get hours
 BNE TIMEOUT if not 0, go
F2 LDA TIMLIM get clock type
 CMP #24 24-hour clock?
 BEQ TIMEOUT yes, go
F3 INC TIME make hours = 1
;
TIMEOUT LDX #0 Init OUTSTR ptr
 LDY #0 start with hours
TOUTLP TYA save Y
 PHA on stack
T3 LDA TIME,Y get time count
 STA NUM save number
 LDY #1 init to 10^1
INLOOP LDA #0 assume zero
 PHA save it
LOOP LDA NUM recover number
T4 CMP POFTEN,Y >= 10^Y?
 BCC NUMOUT No, done
T5 SBC POFTEN,Y Yes, divide by subtraction
 STA NUM save remainder
 PLA count divisions
 SEC add 1 to Acc
 ADC #0
 PHA save again
 BCC LOOP always taken
NUMOUT PLA recover digit (0-9)
 ORA #$30 ASCII "0" + digit
T6 STA OUTSTR,X save ASCII equivalent
 INX next output loc
 DEY next digit
 BPL INLOOP
 INX skip delimiter
 PLA recover Y
 TAY
 INY
 CPY #4 All done?
 BCC TOUTLP No, go again
S1 LDA DSPTGL Yes, display to screen?
 BEQ ALLDONE No, go
 LDY #10 else, 11 chars to go
S2 LDA OUTSTR,Y get char
 STA SCREEN,Y store to screen
 DEY
 BPL S2
ALLDONE CLC mark successful call
;
*=================================
;              Exit
*=================================
;
EXIT DO USER
 JSR USER do User's handler
 ELSE
 NOP
 NOP
 NOP
 FIN
;
 LDA SAVEA recover regs
 STA $45 how we were called...
 LDX SAVEX
 LDY SAVEY
;
 DO PRODOS
 NOP keeps offsets equal
 RTS
;
 ELSE
 CLI for DOS
 RTI
 FIN
;
*=================================
;       Internal variables
*=================================
;
TIMECNT DFB 3
DSPTGL DFB 0 init to off
TIME DFB 0,0,0,0
TIMLIM DFB 24,60,60,100
POFTEN DFB 1,10
 MSB OFF
OUTSTR ASC '00:00:00 00'
PTR DFB 11,>OUTSTR,<OUTSTR
;
*=================================
;Assign OUTSTR to user's variable:
*=================================
;
; Points the user's string variable
; at OUTSTR.  From BASIC:
; LET ASSIGN = Address
; CALL ASSIGN,TIME$
; Then PRINT TIME$ will return
; the current time.  The value of TIME$
; will automatically be updated.
;
ASSIGN JSR CHKCOM check for comma
 JSR PTRGET locate variable
 LDY #2 offset to pointer
ALOOP LDA PTR,Y
 STA (VARPNT),Y
 DEY
 BPL ALOOP
 RTS
;
*=================================
;          Display Switch
*=================================
;
; Calling this routine toggles
; screen display on/off.
;
DISPSWCH LDA DSPTGL get value
 EOR #$FF toggle
S3 STA DSPTGL
 RTS exit
;
*=================================
;         ProDOS TIME call
*=================================
;
; Updates the ProDOS time locations
; when called by the MLI.
;
SAVTIME DO PRODOS
P5 LDA TIME+1
 STA PTIME
P6 LDA TIME
 STA PTIME+1
 RTS
 FIN
;
*=================================
;       Relocation Bytes
*=================================
;
RBYTES DO PRODOS
 DFB 25
;
 ELSE
 DFB 23
 FIN
;
 DFB M1+2,M2+2
 DFB R1+2,R2+2,TIMER+2,T1+2
 DFB TLOOP+2,TLOOP+5,TLOOP+8
 DFB T2+2,F1+2,F2+2,F3+2,T3+2,T4+2,T5+2,T6+2
 DFB S1+2,S2+2,PTR+2
 DFB ALOOP+2,DISPSWCH+2,S3+2
;
 DO PRODOS
 DFB P5+2,P6+2
 FIN