goapple2/source/applesoft/S.EFEA
2014-05-09 17:59:16 -07:00

274 lines
11 KiB
Plaintext

1010 *--------------------------------
1020 * "COS" FUNCTION
1030 *--------------------------------
1040 COS LDA #CON.PI.HALF COS(X)=SIN(X + PI/2)
1050 LDY /CON.PI.HALF
1060 JSR FADD
1070 *--------------------------------
1080 * "SIN" FUNCTION
1090 *--------------------------------
1100 SIN JSR COPY.FAC.TO.ARG.ROUNDED
1110 LDA #CON.PI.DOUB REMOVE MULTIPLES OF 2*PI
1120 LDY /CON.PI.DOUB BY DIVIDING AND SAVING
1130 LDX ARG.SIGN THE FRACTIONAL PART
1140 JSR DIV USE SIGN OF ARGUMENT
1150 JSR COPY.FAC.TO.ARG.ROUNDED
1160 JSR INT TAKE INTEGER PART
1170 LDA #0 <<< WASTED LINES, BECAUSE FSUBT >>>
1180 STA SGNCPR <<< CHANGES SGNCPR AGAIN >>>
1190 JSR FSUBT SUBTRACT TO GET FRACTIONAL PART
1200 *--------------------------------
1210 * (FAC) = ANGLE AS A FRACTION OF A FULL CIRCLE
1220 *
1230 * NOW FOLD THE RANGE INTO A QUARTER CIRCLE
1240 *
1250 * <<< THERE ARE MUCH SIMPLER WAYS TO DO THIS >>>
1260 *--------------------------------
1270 LDA #QUARTER 1/4 - FRACTION MAKES
1280 LDY /QUARTER -3/4 <= FRACTION < 1/4
1290 JSR FSUB
1300 LDA FAC.SIGN TEST SIGN OF RESULT
1310 PHA SAVE SIGN FOR LATER UNFOLDING
1320 BPL SIN.1 ALREADY 0...1/4
1330 JSR FADDH ADD 1/2 TO SHIFT TO -1/4...1/2
1340 LDA FAC.SIGN TEST SIGN
1350 BMI SIN.2 -1/4...0
1360 * 0...1/2
1370 LDA SIGNFLG SIGNFLG INITIALIZED = 0 IN "TAN"
1380 EOR #$FF FUNCTION
1390 STA SIGNFLG "TAN" IS ONLY USER OF SIGNFLG TOO
1400 *--------------------------------
1410 * IF FALL THRU, RANGE IS 0...1/2
1420 * IF BRANCH HERE, RANGE IS 0...1/4
1430 *--------------------------------
1440 SIN.1 JSR NEGOP
1450 *--------------------------------
1460 * IF FALL THRU, RANGE IS -1/2...0
1470 * IF BRANCH HERE, RANGE IS -1/4...0
1480 *--------------------------------
1490 SIN.2 LDA #QUARTER ADD 1/4 TO SHIFT RANGE
1500 LDY /QUARTER TO -1/4...1/4
1510 JSR FADD
1520 PLA GET SAVED SIGN FROM ABOVE
1530 BPL .1
1540 JSR NEGOP MAKE RANGE 0...1/4
1550 .1 LDA #POLY.SIN DO STANDARD SIN SERIES
1560 LDY /POLY.SIN
1570 JMP POLYNOMIAL.ODD
1580 *--------------------------------
1590 * "TAN" FUNCTION
1600 *
1610 * COMPUTE TAN(X) = SIN(X) / COS(X)
1620 *--------------------------------
1630 TAN JSR STORE.FAC.IN.TEMP1.ROUNDED
1640 LDA #0 SIGNFLG WILL BE TOGGLED IF 2ND OR 3RD
1650 STA SIGNFLG QUADRANT
1660 JSR SIN GET SIN(X)
1670 LDX #TEMP3 SAVE SIN(X) IN TEMP3
1680 LDY /TEMP3
1690 JSR GO.MOVMF <<<FUNNY WAY TO CALL MOVMF! >>>
1700 LDA #TEMP1 RETRIEVE X
1710 LDY /TEMP1
1720 JSR LOAD.FAC.FROM.YA
1730 LDA #0 AND COMPUTE COS(X)
1740 STA FAC.SIGN
1750 LDA SIGNFLG
1760 JSR TAN.1 WEIRD & DANGEROUS WAY TO GET INTO SIN
1770 LDA #TEMP3 NOW FORM SIN/COS
1780 LDY /TEMP3
1790 JMP FDIV
1800 *--------------------------------
1810 TAN.1 PHA SHAME, SHAME!
1820 JMP SIN.1
1830 *--------------------------------
1840 CON.PI.HALF .HS 81490FDAA2
1850 CON.PI.DOUB .HS 83490FDAA2
1860 QUARTER .HS 7F00000000
1870 *--------------------------------
1880 POLY.SIN .DA #5 POWER OF POLYNOMIAL
1890 .HS 84E61A2D1B (2PI)^11/11!
1900 .HS 862807FBF8 (2PI)^9/9!
1910 .HS 8799688901 (2PI)^7/7!
1920 .HS 872335DFE1 (2PI)^5/5!
1930 .HS 86A55DE728 (2PI)^3/3!
1940 .HS 83490FDAA2 2PI
1950 *--------------------------------
1960 * <<< NEXT TEN BYTES ARE NEVER REFERENCED >>>
1970 *--------------------------------
1980 .HS A6D3C1C8D4 OR "&SAHT" IN ASCII [exclusive-or each byte with $87 ]
[to get the string "!TFOSORCIM" ]
1990 .HS C8D5C4CECA OR "HUDNJ" IN ASCII [which is "MICROSOFT!" backwards.]
2000 *--------------------------------
2010 * "ATN" FUNCTION
2020 *--------------------------------
2030 ATN LDA FAC.SIGN FOLD THE ARGUMENT RANGE FIRST
2040 PHA SAVE SIGN FOR LATER UNFOLDING
2050 BPL .1 .GE. 0
2060 JSR NEGOP .LT. 0, SO COMPLEMENT
2070 .1 LDA FAC IF .GE. 1, FORM RECIPROCAL
2080 PHA SAVE FOR LATER UNFOLDING
2090 CMP #$81 (EXPONENT FOR .GE. 1
2100 BCC .2 X < 1
2110 LDA #CON.ONE FORM 1/X
2120 LDY /CON.ONE
2130 JSR FDIV
2140 *--------------------------------
2150 * 0 <= X <= 1
2160 * 0 <= ATN(X) <= PI/8
2170 *--------------------------------
2180 .2 LDA #POLY.ATN COMPUTE POLYNOMIAL APPROXIMATION
2190 LDY /POLY.ATN
2200 JSR POLYNOMIAL.ODD
2210 PLA START TO UNFOLD
2220 CMP #$81 WAS IT .GE. 1?
2230 BCC .3 NO
2240 LDA #CON.PI.HALF YES, SUBTRACT FROM PI/2
2250 LDY /CON.PI.HALF
2260 JSR FSUB
2270 .3 PLA WAS IT NEGATIVE?
2280 BPL RTS.20 NO
2290 JMP NEGOP YES, COMPLEMENT
2300 RTS.20 RTS
2310 *--------------------------------
2320 POLY.ATN .DA #11 POWER OF POLYNOMIAL
2330 .HS 76B383BDD3
2340 .HS 791EF4A6F5
2350 .HS 7B83FCB010
2360 .HS 7C0C1F67CA
2370 .HS 7CDE53CBC1
2380 .HS 7D1464704C
2390 .HS 7DB7EA517A
2400 .HS 7D6330887E
2410 .HS 7E9244993A
2420 .HS 7E4CCC91C7
2430 .HS 7FAAAAAA13
2440 .HS 8100000000
2450 *--------------------------------
2460 * GENERIC COPY OF CHRGET SUBROUTINE, WHICH
2470 * IS COPIED INTO $00B1...$00C8 DURING INITIALIZATION
2480 *
2490 * CORNELIS BONGERS DESCRIBED SEVERAL IMPROVEMENTS
2500 * TO CHRGET IN MICRO MAGAZINE OR CALL A.P.P.L.E.
2510 * (I DON'T REMEMBER WHICH OR EXACTLY WHEN)
2520 *--------------------------------
2530 GENERIC.CHRGET
2540 INC TXTPTR
2550 BNE .1
2560 INC TXTPTR+1
2570 .1 LDA $EA60 <<< ACTUAL ADDRESS FILLED IN LATER >>>
2580 CMP #':' EOS, ALSO TOP OF NUMERIC RANGE
2590 BCS .2 NOT NUMBER, MIGHT BE EOS
2600 CMP #' ' IGNORE BLANKS
2610 BEQ GENERIC.CHRGET
2620 SEC TEST FOR NUMERIC RANGE IN WAY THAT
2630 SBC #'0' CLEARS CARRY IF CHAR IS DIGIT
2640 SEC AND LEAVES CHAR IN A-REG
2650 SBC #-'0'
2660 .2 RTS
2670 *--------------------------------
2680 * INITIAL VALUE FOR RANDOM NUMBER, ALSO COPIED
2690 * IN ALONG WITH CHRGET, BUT ERRONEOUSLY:
2700 * <<< THE LAST BYTE IS NOT COPIED >>>
2710 *--------------------------------
2720 .HS 804FC75258 APPROX. = .811635157
2730 GENERIC.END
2740 *--------------------------------
2750 COLD.START
2760 LDX #$FF SET DIRECT MODE FLAG
2770 STX CURLIN+1
2780 LDX #$FB SET STACK POINTER, LEAVING ROOM FOR
2790 TXS LINE BUFFER DURING PARSING
2800 LDA #COLD.START SET RESTART TO COLD.START
2810 LDY /COLD.START UNTIL COLDSTART IS COMPLETED
2820 STA GOWARM+1
2830 STY GOWARM+2
2840 STA GOSTROUT+1 ALSO SECOND USER VECTOR...
2850 STY GOSTROUT+2 ..WE SIMPLY MUST FINISH COLD.START!
2860 JSR NORMAL SET NORMAL DISPLAY MODE
2870 LDA #$4C "JMP" OPCODE FOR 4 VECTORS
2880 STA GOWARM WARM START
2890 STA GOSTROUT ANYONE EVER USE THIS ONE?
2900 STA JMPADRS USED BY FUNCTIONS (JSR JMPADRS)
2910 STA USR "USR" FUNCTION VECTOR
2920 LDA #IQERR POINT "USR" TO ILLEGAL QUANTITY
2930 LDY /IQERR ERROR, UNTIL USER SETS IT UP
2940 STA USR+1
2950 STY USR+2
2960 *--------------------------------
2970 * MOVE GENERIC CHRGET AND RANDOM SEED INTO PLACE
2980 *
2990 * <<< NOTE THAT LOOP VALUE IS WRONG! >>>
3000 * <<< THE LAST BYTE OF THE RANDOM SEED IS NOT >>>
3010 * <<< COPIED INTO PAGE ZERO! >>>
3020 *--------------------------------
3030 LDX #GENERIC.END-GENERIC.CHRGET-1
3040 .1 LDA GENERIC.CHRGET-1,X
3050 STA CHRGET-1,X
3060 STX SPEEDZ ON LAST PASS STORES $01)
3070 DEX
3080 BNE .1
3090 *--------------------------------
3100 STX TRCFLG X=0, TURN OFF TRACING
3110 TXA A=0
3120 STA SHIFT.SIGN.EXT
3130 STA LASTPT+1
3140 PHA PUT $00 ON STACK (WHAT FOR?)
3150 LDA #3 SET LENGTH OF TEMP. STRING DESCRIPTORS
3160 STA DSCLEN FOR GARBAGE COLLECTION SUBROUTINE
3170 JSR CRDO PRINT <RETURN>
3180 LDA #1 SET UP FAKE FORWARD LINK
3190 STA INPUT.BUFFER-3
3200 STA INPUT.BUFFER-4
3210 LDX #TEMPST INIT INDEX TO TEMP STRING DESCRIPTORS
3220 STX TEMPPT
3230 *--------------------------------
3240 * FIND HIGH END OF RAM
3250 *--------------------------------
3260 LDA #$0800 SET UP POINTER TO LOW END OF RAM
3270 LDY /$0800
3280 STA LINNUM
3290 STY LINNUM+1
3300 LDY #0
3310 .2 INC LINNUM+1 TEST FIRST BYTE OF EACH PAGE
3320 LDA (LINNUM),Y BY COMPLEMENTING IT AND WATCHING
3330 EOR #$FF IT CHANGE THE SAME WAY
3340 STA (LINNUM),Y
3350 CMP (LINNUM),Y ROM OR EMPTY SOCKETS WON'T TRACK
3360 BNE .3 NOT RAM HERE
3370 EOR #$FF RESTORE ORIGINAL VALUE
3380 STA (LINNUM),Y
3390 CMP (LINNUM),Y DID IT TRACK AGAIN?
3400 BEQ .2 YES, STILL IN RAM
3410 .3 LDY LINNUM NO, END OF RAM
3420 LDA LINNUM+1
3430 AND #$F0 FORCE A MULTIPLE OF 4096 BYTES
3440 STY MEMSIZ (BAD RAM MAY HAVE YIELDED NON-MULTIPLE)
3450 STA MEMSIZ+1
3460 STY FRETOP SET HIMEM AND BOTTOM OF STRINGS
3470 STA FRETOP+1
3480 LDX #$0800 SET PROGRAM POINTER TO $0800
3490 LDY /$0800
3500 STX TXTTAB
3510 STY TXTTAB+1
3520 LDY #0 TURN OFF SEMI-SECRET LOCK FLAG
3530 STY LOCK
3540 TYA A=0 TOO
3550 STA (TXTTAB),Y FIRST BYTE IN PROGRAM SPACE = 0
3560 INC TXTTAB ADVANCE PAST THE $00
3570 BNE .4
3580 INC TXTTAB+1
3590 .4 LDA TXTTAB
3600 LDY TXTTAB+1
3610 JSR REASON SET REST OF POINTERS UP
3620 JSR SCRTCH MORE POINTERS
3630 LDA #STROUT PUT CORRECT ADDRESSES IN TWO
3640 LDY /STROUT USER VECTORS
3650 STA GOSTROUT+1
3660 STY GOSTROUT+2
3670 LDA #RESTART
3680 LDY /RESTART
3690 STA GOWARM+1
3700 STY GOWARM+2
3710 JMP (GOWARM+1) SILLY, WHY NOT JUST "JMP RESTART"
3720 *--------------------------------