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New folder, Floating Point operation.

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rigreco 2015-02-15 15:10:16 +01:00
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163
AppleII/FP operations/UniFP.asm Normal file
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* @com.wudsn.ide.asm.hardware=APPLE2
***********************
* *
* APPLE-II FLOATING *
* POINT ROUTINES *
* *
* COPYRIGHT 1977 BY *
* APPLE COMPUTER INC. *
* *
* ALL RIGHTS RESERVED *
* *
* S. WOZNIAK *
* *
***********************
* TITLE "FLOATING POINT ROUTINES for //c memory"
*
SIGN EQU $EB ; $F3
** FP2 4 Bytes **
X2 EQU $EC ; $F4
M2 EQU $ED ; $F5 - $7
** FP1 4 Bytes + E extension **
X1 EQU $FA ; $F8
M1 EQU $FB ; $F9 - $FB
E EQU $FE ; $FC
OVLOC EQU $3F5
ORG $300
ADD CLC ;CLEAR CARRY
LDX #$2 ;INDEX FOR 3-BYTE ADD.
ADD1 LDA M1,X
ADC M2,X ;ADD A BYTE OF MANT2 TO MANT1
STA M1,X
DEX ;INDEX TO NEXT MORE SIGNIF. BYTE.
BPL ADD1 ;LOOP UNTIL DONE.
RTS ;RETURN
MD1 ASL SIGN ;CLEAR LSB OF SIGN.
JSR ABSWAP ;ABS VAL OF M1, THEN SWAP WITH M2
ABSWAP BIT M1 ;MANT1 NEGATIVE?
BPL ABSWAP1 ;NO, SWAP WITH MANT2 AND RETURN.
JSR FCOMPL ;YES, COMPLEMENT IT.
INC SIGN ;INCR SIGN, COMPLEMENTING LSB.
ABSWAP1 SEC ;SET CARRY FOR RETURN TO MUL/DIV.
SWAP LDX #$4 ;INDEX FOR 4 BYTE SWAP.
SWAP1 STY E-1,X
LDA X1-1,X ;SWAP A BYTE OF EXP/MANT1 WITH
LDY X2-1,X ;EXP/MANT2 AND LEAVE A COPY OF
STY X1-1,X ;MANT1 IN E (3 BYTES). E+3 USED
STA X2-1,X
DEX ;ADVANCE INDEX TO NEXT BYTE
BNE SWAP1 ;LOOP UNTIL DONE.
RTS ;RETURN
FLOAT LDA #$8E ;INIT EXP1 TO 14, <--------------- int to fp
STA X1 ;THEN NORMALIZE TO FLOAT.
NORM1 LDA M1 ;HIGH-ORDER MANT1 BYTE.
CMP #$C0 ;UPPER TWO BITS UNEQUAL?
BMI RTS1 ;YES, RETURN WITH MANT1 NORMALIZED
DEC X1 ;DECREMENT EXP1.
ASL M1+2
ROL M1+1 ;SHIFT MANT1 (3 BYTES) LEFT.
ROL M1
NORM LDA X1 ;EXP1 ZERO?
BNE NORM1 ;NO, CONTINUE NORMALIZING.
RTS1 RTS ;RETURN.
FSUB JSR FCOMPL ;CMPL MANT1,CLEARS CARRY UNLESS 0 <---- sub
SWPALGN JSR ALGNSWP ;RIGHT SHIFT MANT1 OR SWAP WITH
FADD LDA X2 ;<------------------------------------- add
CMP X1 ;COMPARE EXP1 WITH EXP2.
BNE SWPALGN ;IF #,SWAP ADDENDS OR ALIGN MANTS.
JSR ADD ;ADD ALIGNED MANTISSAS.
ADDEND BVC NORM ;NO OVERFLOW, NORMALIZE RESULT.
BVS RTLOG ;OV: SHIFT M1 RIGHT, CARRY INTO SIGN
ALGNSWP BCC SWAP ;SWAP IF CARRY CLEAR,
* ELSE SHIFT RIGHT ARITH.
RTAR LDA M1 ;SIGN OF MANT1 INTO CARRY FOR
ASL ;RIGHT ARITH SHIFT.
RTLOG INC X1 ;INCR X1 TO ADJUST FOR RIGHT SHIFT
BEQ OVFL ;EXP1 OUT OF RANGE.
RTLOG1 LDX #$FA ;INDEX FOR 6:BYTE RIGHT SHIFT.
ROR1 ROR E+3,X
INX ;NEXT BYTE OF SHIFT.
BNE ROR1 ;LOOP UNTIL DONE.
RTS ;RETURN.
FMUL JSR MD1 ;ABS VAL OF MANT1, MANT2 <-------------- mul
ADC X1 ;ADD EXP1 TO EXP2 FOR PRODUCT EXP
JSR MD2 ;CHECK PROD. EXP AND PREP. FOR MUL
CLC ;CLEAR CARRY FOR FIRST BIT.
MUL1 JSR RTLOG1 ;M1 AND E RIGHT (PROD AND MPLIER)
BCC MUL2 ;IF CARRY CLEAR, SKIP PARTIAL PROD
JSR ADD ;ADD MULTIPLICAND TO PRODUCT.
MUL2 DEY ;NEXT MUL ITERATION.
BPL MUL1 ;LOOP UNTIL DONE.
MDEND LSR SIGN ;TEST SIGN LSB.
NORMX BCC NORM ;IF EVEN,NORMALIZE PROD,ELSE COMP
FCOMPL SEC ;SET CARRY FOR SUBTRACT. <--------------- not
LDX #$3 ;INDEX FOR 3 BYTE SUBTRACT.
COMPL1 LDA #$0 ;CLEAR A.
SBC X1,X ;SUBTRACT BYTE OF EXP1.
STA X1,X ;RESTORE IT.
DEX ;NEXT MORE SIGNIFICANT BYTE.
BNE COMPL1 ;LOOP UNTIL DONE.
BEQ ADDEND ;NORMALIZE (OR SHIFT RT IF OVFL).
FDIV JSR MD1 ;TAKE ABS VAL OF MANT1, MANT2. <--------- div
SBC X1 ;SUBTRACT EXP1 FROM EXP2.
JSR MD2 ;SAVE AS QUOTIENT EXP.
DIV1 SEC ;SET CARRY FOR SUBTRACT.
LDX #$2 ;INDEX FOR 3-BYTE SUBTRACTION.
DIV2 LDA M2,X
SBC E,X ;SUBTRACT A BYTE OF E FROM MANT2.
PHA ;SAVE ON STACK.
DEX ;NEXT MORE SIGNIFICANT BYTE.
BPL DIV2 ;LOOP UNTIL DONE.
LDX #$FD ;INDEX FOR 3-BYTE CONDITIONAL MOVE
DIV3 PLA ;PULL BYTE OF DIFFERENCE OFF STACK
BCC DIV4 ;IF M2<E THEN DON'T RESTORE M2.
STA M2+3,X
DIV4 INX ;NEXT LESS SIGNIFICANT BYTE.
BNE DIV3 ;LOOP UNTIL DONE.
ROL M1+2
ROL M1+1 ;ROLL QUOTIENT LEFT, CARRY INTO LSB
ROL M1
ASL M2+2
ROL M2+1 ;SHIFT DIVIDEND LEFT
ROL M2
BCS OVFL ;OVFL IS DUE TO UNNORMED DIVISOR
DEY ;NEXT DIVIDE ITERATION.
BNE DIV1 ;LOOP UNTIL DONE 23 ITERATIONS.
BEQ MDEND ;NORM. QUOTIENT AND CORRECT SIGN.
MD2 STX M1+2
STX M1+1 ;CLEAR MANT1 (3 BYTES) FOR MUL/DIV.
STX M1
BCS OVCHK ;IF CALC. SET CARRY,CHECK FOR OVFL
BMI MD3 ;IF NEG THEN NO UNDERFLOW.
PLA ;POP ONE RETURN LEVEL.
PLA
BCC NORMX ;CLEAR X1 AND RETURN.
MD3 EOR #$80 ;COMPLEMENT SIGN BIT OF EXPONENT.
STA X1 ;STORE IT.
LDY #$17 ;COUNT 24 MUL/23 DIV ITERATIONS.
RTS ;RETURN.
OVCHK BPL MD3 ;IF POSITIVE EXP THEN NO OVFL.
OVFL JMP OVLOC
* ORG $F63D
FIX1 JSR RTAR
FIX LDA X1 ; <------------------------------ fp to int
BPL UNDFL
CMP #$8E
BNE FIX1
BIT M1
BPL FIXRTS
LDA M1+2
BEQ FIXRTS
INC M1+1
BNE FIXRTS
INC M1
FIXRTS RTS
UNDFL LDA #$0
STA M1
STA M1+1
RTS

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AppleII/FP operations/UniFP_Output.txt Normal file
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------+---------------------+-------------+----+---------+------+-----------------------+-------------------------------------------------------------------
Line | # File Line | Line Type | MX | Reloc | Size | Address Object Code | Source Code
------+---------------------+-------------+----+---------+------+-----------------------+-------------------------------------------------------------------
1 | 1 UniFP.asm 1 | Comment | 11 | | 0 | 00/8000 | * @com.wudsn.ide.asm.hardware=APPLE2
2 | 1 UniFP.asm 2 | Comment | 11 | | 0 | 00/8000 | ***********************
3 | 1 UniFP.asm 3 | Comment | 11 | | 0 | 00/8000 | * *
4 | 1 UniFP.asm 4 | Comment | 11 | | 0 | 00/8000 | * APPLE-II FLOATING *
5 | 1 UniFP.asm 5 | Comment | 11 | | 0 | 00/8000 | * POINT ROUTINES *
6 | 1 UniFP.asm 6 | Comment | 11 | | 0 | 00/8000 | * *
7 | 1 UniFP.asm 7 | Comment | 11 | | 0 | 00/8000 | * COPYRIGHT 1977 BY *
8 | 1 UniFP.asm 8 | Comment | 11 | | 0 | 00/8000 | * APPLE COMPUTER INC. *
9 | 1 UniFP.asm 9 | Comment | 11 | | 0 | 00/8000 | * *
10 | 1 UniFP.asm 10 | Comment | 11 | | 0 | 00/8000 | * ALL RIGHTS RESERVED *
11 | 1 UniFP.asm 11 | Comment | 11 | | 0 | 00/8000 | * *
12 | 1 UniFP.asm 12 | Comment | 11 | | 0 | 00/8000 | * S. WOZNIAK *
13 | 1 UniFP.asm 13 | Comment | 11 | | 0 | 00/8000 | * *
14 | 1 UniFP.asm 14 | Comment | 11 | | 0 | 00/8000 | ***********************
15 | 1 UniFP.asm 15 | Comment | 11 | | 0 | 00/8000 | * TITLE "FLOATING POINT ROUTINES for //c memory"
16 | 1 UniFP.asm 16 | Comment | 11 | | 0 | 00/8000 | *
17 | 1 UniFP.asm 17 | Equivalence | 11 | | 0 | 00/8000 | SIGN EQU $EB ; $F3
18 | 1 UniFP.asm 18 | Empty | 11 | | 0 | 00/8000 |
19 | 1 UniFP.asm 19 | Comment | 11 | | 0 | 00/8000 | ** FP2 4 Bytes **
20 | 1 UniFP.asm 20 | Equivalence | 11 | | 0 | 00/8000 | X2 EQU $EC ; $F4
21 | 1 UniFP.asm 21 | Equivalence | 11 | | 0 | 00/8000 | M2 EQU $ED ; $F5 - $7
22 | 1 UniFP.asm 22 | Empty | 11 | | 0 | 00/8000 |
23 | 1 UniFP.asm 23 | Comment | 11 | | 0 | 00/8000 | ** FP1 4 Bytes + E extension **
24 | 1 UniFP.asm 24 | Equivalence | 11 | | 0 | 00/8000 | X1 EQU $FA ; $F8
25 | 1 UniFP.asm 25 | Equivalence | 11 | | 0 | 00/8000 | M1 EQU $FB ; $F9 - $FB
26 | 1 UniFP.asm 26 | Equivalence | 11 | | 0 | 00/8000 | E EQU $FE ; $FC
27 | 1 UniFP.asm 27 | Empty | 11 | | 0 | 00/8000 |
28 | 1 UniFP.asm 28 | Equivalence | 11 | | 0 | 00/8000 | OVLOC EQU $3F5
29 | 1 UniFP.asm 29 | Empty | 11 | | 0 | 00/8000 |
30 | 1 UniFP.asm 30 | Directive | 11 | | 0 | 00/8000 | ORG $300
31 | 1 UniFP.asm 31 | Empty | 11 | | 0 | 00/0300 |
32 | 1 UniFP.asm 32 | Code | 11 | | 1 | 00/0300 : 18 | ADD CLC ;CLEAR CARRY
33 | 1 UniFP.asm 33 | Code | 11 | | 2 | 00/0301 : A2 02 | LDX #$2 ;INDEX FOR 3-BYTE ADD.
34 | 1 UniFP.asm 34 | Code | 11 | | 2 | 00/0303 : B5 FB | ADD1 LDA {$FB},X
35 | 1 UniFP.asm 35 | Code | 11 | | 2 | 00/0305 : 75 ED | ADC {$ED},X ;ADD A BYTE OF MANT2 TO MANT1
36 | 1 UniFP.asm 36 | Code | 11 | | 2 | 00/0307 : 95 FB | STA {$FB},X
37 | 1 UniFP.asm 37 | Code | 11 | | 1 | 00/0309 : CA | DEX ;INDEX TO NEXT MORE SIGNIF. BYTE.
38 | 1 UniFP.asm 38 | Code | 11 | | 2 | 00/030A : 10 F7 | BPL ADD1 ;LOOP UNTIL DONE.
39 | 1 UniFP.asm 39 | Code | 11 | | 1 | 00/030C : 60 | RTS ;RETURN
40 | 1 UniFP.asm 40 | Code | 11 | | 2 | 00/030D : 06 EB | MD1 ASL {$EB} ;CLEAR LSB OF SIGN.
41 | 1 UniFP.asm 41 | Code | 11 | | 3 | 00/030F : 20 12 03 | JSR ABSWAP ;ABS VAL OF M1, THEN SWAP WITH M2
42 | 1 UniFP.asm 42 | Code | 11 | | 2 | 00/0312 : 24 FB | ABSWAP BIT {$FB} ;MANT1 NEGATIVE?
43 | 1 UniFP.asm 43 | Code | 11 | | 2 | 00/0314 : 10 05 | BPL ABSWAP1 ;NO, SWAP WITH MANT2 AND RETURN.
44 | 1 UniFP.asm 44 | Code | 11 | | 3 | 00/0316 : 20 7F 03 | JSR FCOMPL ;YES, COMPLEMENT IT.
45 | 1 UniFP.asm 45 | Code | 11 | | 2 | 00/0319 : E6 EB | INC {$EB} ;INCR SIGN, COMPLEMENTING LSB.
46 | 1 UniFP.asm 46 | Code | 11 | | 1 | 00/031B : 38 | ABSWAP1 SEC ;SET CARRY FOR RETURN TO MUL/DIV.
47 | 1 UniFP.asm 47 | Code | 11 | | 2 | 00/031C : A2 04 | SWAP LDX #$4 ;INDEX FOR 4 BYTE SWAP.
48 | 1 UniFP.asm 48 | Code | 11 | | 2 | 00/031E : 94 FD | SWAP1 STY {$FE}-1,X
49 | 1 UniFP.asm 49 | Code | 11 | | 2 | 00/0320 : B5 F9 | LDA {$FA}-1,X ;SWAP A BYTE OF EXP/MANT1 WITH
50 | 1 UniFP.asm 50 | Code | 11 | | 2 | 00/0322 : B4 EB | LDY {$EC}-1,X ;EXP/MANT2 AND LEAVE A COPY OF
51 | 1 UniFP.asm 51 | Code | 11 | | 2 | 00/0324 : 94 F9 | STY {$FA}-1,X ;MANT1 IN E (3 BYTES). E+3 USED
52 | 1 UniFP.asm 52 | Code | 11 | | 2 | 00/0326 : 95 EB | STA {$EC}-1,X
53 | 1 UniFP.asm 53 | Code | 11 | | 1 | 00/0328 : CA | DEX ;ADVANCE INDEX TO NEXT BYTE
54 | 1 UniFP.asm 54 | Code | 11 | | 2 | 00/0329 : D0 F3 | BNE SWAP1 ;LOOP UNTIL DONE.
55 | 1 UniFP.asm 55 | Code | 11 | | 1 | 00/032B : 60 | RTS ;RETURN
56 | 1 UniFP.asm 56 | Code | 11 | | 2 | 00/032C : A9 8E | FLOAT LDA #$8E ;INIT EXP1 TO 14, <--------------- int to fp
57 | 1 UniFP.asm 57 | Code | 11 | | 2 | 00/032E : 85 FA | STA {$FA} ;THEN NORMALIZE TO FLOAT.
58 | 1 UniFP.asm 58 | Code | 11 | | 2 | 00/0330 : A5 FB | NORM1 LDA {$FB} ;HIGH-ORDER MANT1 BYTE.
59 | 1 UniFP.asm 59 | Code | 11 | | 2 | 00/0332 : C9 C0 | CMP #$C0 ;UPPER TWO BITS UNEQUAL?
60 | 1 UniFP.asm 60 | Code | 11 | | 2 | 00/0334 : 30 0C | BMI RTS1 ;YES, RETURN WITH MANT1 NORMALIZED
61 | 1 UniFP.asm 61 | Code | 11 | | 2 | 00/0336 : C6 FA | DEC {$FA} ;DECREMENT EXP1.
62 | 1 UniFP.asm 62 | Code | 11 | | 2 | 00/0338 : 06 FD | ASL {$FB}+2
63 | 1 UniFP.asm 63 | Code | 11 | | 2 | 00/033A : 26 FC | ROL {$FB}+1 ;SHIFT MANT1 (3 BYTES) LEFT.
64 | 1 UniFP.asm 64 | Code | 11 | | 2 | 00/033C : 26 FB | ROL {$FB}
65 | 1 UniFP.asm 65 | Code | 11 | | 2 | 00/033E : A5 FA | NORM LDA {$FA} ;EXP1 ZERO?
66 | 1 UniFP.asm 66 | Code | 11 | | 2 | 00/0340 : D0 EE | BNE NORM1 ;NO, CONTINUE NORMALIZING.
67 | 1 UniFP.asm 67 | Code | 11 | | 1 | 00/0342 : 60 | RTS1 RTS ;RETURN.
68 | 1 UniFP.asm 68 | Code | 11 | | 3 | 00/0343 : 20 7F 03 | FSUB JSR FCOMPL ;CMPL MANT1,CLEARS CARRY UNLESS 0 <---- sub
69 | 1 UniFP.asm 69 | Code | 11 | | 3 | 00/0346 : 20 56 03 | SWPALGN JSR ALGNSWP ;RIGHT SHIFT MANT1 OR SWAP WITH
70 | 1 UniFP.asm 70 | Code | 11 | | 2 | 00/0349 : A5 EC | FADD LDA {$EC} ;<------------------------------------- add
71 | 1 UniFP.asm 71 | Code | 11 | | 2 | 00/034B : C5 FA | CMP {$FA} ;COMPARE EXP1 WITH EXP2.
72 | 1 UniFP.asm 72 | Code | 11 | | 2 | 00/034D : D0 F7 | BNE SWPALGN ;IF #,SWAP ADDENDS OR ALIGN MANTS.
73 | 1 UniFP.asm 73 | Code | 11 | | 3 | 00/034F : 20 00 03 | JSR ADD ;ADD ALIGNED MANTISSAS.
74 | 1 UniFP.asm 74 | Code | 11 | | 2 | 00/0352 : 50 EA | ADDEND BVC NORM ;NO OVERFLOW, NORMALIZE RESULT.
75 | 1 UniFP.asm 75 | Code | 11 | | 2 | 00/0354 : 70 05 | BVS RTLOG ;OV: SHIFT M1 RIGHT, CARRY INTO SIGN
76 | 1 UniFP.asm 76 | Code | 11 | | 2 | 00/0356 : 90 C4 | ALGNSWP BCC SWAP ;SWAP IF CARRY CLEAR,
77 | 1 UniFP.asm 77 | Comment | 11 | | 0 | 00/0358 | * ELSE SHIFT RIGHT ARITH.
78 | 1 UniFP.asm 78 | Code | 11 | | 2 | 00/0358 : A5 FB | RTAR LDA {$FB} ;SIGN OF MANT1 INTO CARRY FOR
79 | 1 UniFP.asm 79 | Code | 11 | | 1 | 00/035A : 0A | ASL ;RIGHT ARITH SHIFT.
80 | 1 UniFP.asm 80 | Code | 11 | | 2 | 00/035B : E6 FA | RTLOG INC {$FA} ;INCR X1 TO ADJUST FOR RIGHT SHIFT
81 | 1 UniFP.asm 81 | Code | 11 | | 2 | 00/035D : F0 75 | BEQ OVFL ;EXP1 OUT OF RANGE.
82 | 1 UniFP.asm 82 | Code | 11 | | 2 | 00/035F : A2 FA | RTLOG1 LDX #$FA ;INDEX FOR 6:BYTE RIGHT SHIFT.
83 | 1 UniFP.asm 83 | Code | 11 | | 2 | 00/0361 : 76 01 | ROR1 ROR {$FE}+3,X
84 | 1 UniFP.asm 84 | Code | 11 | | 1 | 00/0363 : E8 | INX ;NEXT BYTE OF SHIFT.
85 | 1 UniFP.asm 85 | Code | 11 | | 2 | 00/0364 : D0 FB | BNE ROR1 ;LOOP UNTIL DONE.
86 | 1 UniFP.asm 86 | Code | 11 | | 1 | 00/0366 : 60 | RTS ;RETURN.
87 | 1 UniFP.asm 87 | Code | 11 | | 3 | 00/0367 : 20 0D 03 | FMUL JSR MD1 ;ABS VAL OF MANT1, MANT2 <-------------- mul
88 | 1 UniFP.asm 88 | Code | 11 | | 2 | 00/036A : 65 FA | ADC {$FA} ;ADD EXP1 TO EXP2 FOR PRODUCT EXP
89 | 1 UniFP.asm 89 | Code | 11 | | 3 | 00/036C : 20 BD 03 | JSR MD2 ;CHECK PROD. EXP AND PREP. FOR MUL
90 | 1 UniFP.asm 90 | Code | 11 | | 1 | 00/036F : 18 | CLC ;CLEAR CARRY FOR FIRST BIT.
91 | 1 UniFP.asm 91 | Code | 11 | | 3 | 00/0370 : 20 5F 03 | MUL1 JSR RTLOG1 ;M1 AND E RIGHT (PROD AND MPLIER)
92 | 1 UniFP.asm 92 | Code | 11 | | 2 | 00/0373 : 90 03 | BCC MUL2 ;IF CARRY CLEAR, SKIP PARTIAL PROD
93 | 1 UniFP.asm 93 | Code | 11 | | 3 | 00/0375 : 20 00 03 | JSR ADD ;ADD MULTIPLICAND TO PRODUCT.
94 | 1 UniFP.asm 94 | Code | 11 | | 1 | 00/0378 : 88 | MUL2 DEY ;NEXT MUL ITERATION.
95 | 1 UniFP.asm 95 | Code | 11 | | 2 | 00/0379 : 10 F5 | BPL MUL1 ;LOOP UNTIL DONE.
96 | 1 UniFP.asm 96 | Code | 11 | | 2 | 00/037B : 46 EB | MDEND LSR {$EB} ;TEST SIGN LSB.
97 | 1 UniFP.asm 97 | Code | 11 | | 2 | 00/037D : 90 BF | NORMX BCC NORM ;IF EVEN,NORMALIZE PROD,ELSE COMP
98 | 1 UniFP.asm 98 | Code | 11 | | 1 | 00/037F : 38 | FCOMPL SEC ;SET CARRY FOR SUBTRACT. <--------------- not
99 | 1 UniFP.asm 99 | Code | 11 | | 2 | 00/0380 : A2 03 | LDX #$3 ;INDEX FOR 3 BYTE SUBTRACT.
100 | 1 UniFP.asm 100 | Code | 11 | | 2 | 00/0382 : A9 00 | COMPL1 LDA #$0 ;CLEAR A.
101 | 1 UniFP.asm 101 | Code | 11 | | 2 | 00/0384 : F5 FA | SBC {$FA},X ;SUBTRACT BYTE OF EXP1.
102 | 1 UniFP.asm 102 | Code | 11 | | 2 | 00/0386 : 95 FA | STA {$FA},X ;RESTORE IT.
103 | 1 UniFP.asm 103 | Code | 11 | | 1 | 00/0388 : CA | DEX ;NEXT MORE SIGNIFICANT BYTE.
104 | 1 UniFP.asm 104 | Code | 11 | | 2 | 00/0389 : D0 F7 | BNE COMPL1 ;LOOP UNTIL DONE.
105 | 1 UniFP.asm 105 | Code | 11 | | 2 | 00/038B : F0 C5 | BEQ ADDEND ;NORMALIZE (OR SHIFT RT IF OVFL).
106 | 1 UniFP.asm 106 | Code | 11 | | 3 | 00/038D : 20 0D 03 | FDIV JSR MD1 ;TAKE ABS VAL OF MANT1, MANT2. <--------- div
107 | 1 UniFP.asm 107 | Code | 11 | | 2 | 00/0390 : E5 FA | SBC {$FA} ;SUBTRACT EXP1 FROM EXP2.
108 | 1 UniFP.asm 108 | Code | 11 | | 3 | 00/0392 : 20 BD 03 | JSR MD2 ;SAVE AS QUOTIENT EXP.
109 | 1 UniFP.asm 109 | Code | 11 | | 1 | 00/0395 : 38 | DIV1 SEC ;SET CARRY FOR SUBTRACT.
110 | 1 UniFP.asm 110 | Code | 11 | | 2 | 00/0396 : A2 02 | LDX #$2 ;INDEX FOR 3-BYTE SUBTRACTION.
111 | 1 UniFP.asm 111 | Code | 11 | | 2 | 00/0398 : B5 ED | DIV2 LDA {$ED},X
112 | 1 UniFP.asm 112 | Code | 11 | | 2 | 00/039A : F5 FE | SBC {$FE},X ;SUBTRACT A BYTE OF E FROM MANT2.
113 | 1 UniFP.asm 113 | Code | 11 | | 1 | 00/039C : 48 | PHA ;SAVE ON STACK.
114 | 1 UniFP.asm 114 | Code | 11 | | 1 | 00/039D : CA | DEX ;NEXT MORE SIGNIFICANT BYTE.
115 | 1 UniFP.asm 115 | Code | 11 | | 2 | 00/039E : 10 F8 | BPL DIV2 ;LOOP UNTIL DONE.
116 | 1 UniFP.asm 116 | Code | 11 | | 2 | 00/03A0 : A2 FD | LDX #$FD ;INDEX FOR 3-BYTE CONDITIONAL MOVE
117 | 1 UniFP.asm 117 | Code | 11 | | 1 | 00/03A2 : 68 | DIV3 PLA ;PULL BYTE OF DIFFERENCE OFF STACK
118 | 1 UniFP.asm 118 | Code | 11 | | 2 | 00/03A3 : 90 02 | BCC DIV4 ;IF M2<E THEN DON'T RESTORE M2.
119 | 1 UniFP.asm 119 | Code | 11 | | 2 | 00/03A5 : 95 F0 | STA {$ED}+3,X
120 | 1 UniFP.asm 120 | Code | 11 | | 1 | 00/03A7 : E8 | DIV4 INX ;NEXT LESS SIGNIFICANT BYTE.
121 | 1 UniFP.asm 121 | Code | 11 | | 2 | 00/03A8 : D0 F8 | BNE DIV3 ;LOOP UNTIL DONE.
122 | 1 UniFP.asm 122 | Code | 11 | | 2 | 00/03AA : 26 FD | ROL {$FB}+2
123 | 1 UniFP.asm 123 | Code | 11 | | 2 | 00/03AC : 26 FC | ROL {$FB}+1 ;ROLL QUOTIENT LEFT, CARRY INTO LSB
124 | 1 UniFP.asm 124 | Code | 11 | | 2 | 00/03AE : 26 FB | ROL {$FB}
125 | 1 UniFP.asm 125 | Code | 11 | | 2 | 00/03B0 : 06 EF | ASL {$ED}+2
126 | 1 UniFP.asm 126 | Code | 11 | | 2 | 00/03B2 : 26 EE | ROL {$ED}+1 ;SHIFT DIVIDEND LEFT
127 | 1 UniFP.asm 127 | Code | 11 | | 2 | 00/03B4 : 26 ED | ROL {$ED}
128 | 1 UniFP.asm 128 | Code | 11 | | 2 | 00/03B6 : B0 1C | BCS OVFL ;OVFL IS DUE TO UNNORMED DIVISOR
129 | 1 UniFP.asm 129 | Code | 11 | | 1 | 00/03B8 : 88 | DEY ;NEXT DIVIDE ITERATION.
130 | 1 UniFP.asm 130 | Code | 11 | | 2 | 00/03B9 : D0 DA | BNE DIV1 ;LOOP UNTIL DONE 23 ITERATIONS.
131 | 1 UniFP.asm 131 | Code | 11 | | 2 | 00/03BB : F0 BE | BEQ MDEND ;NORM. QUOTIENT AND CORRECT SIGN.
132 | 1 UniFP.asm 132 | Code | 11 | | 2 | 00/03BD : 86 FD | MD2 STX {$FB}+2
133 | 1 UniFP.asm 133 | Code | 11 | | 2 | 00/03BF : 86 FC | STX {$FB}+1 ;CLEAR MANT1 (3 BYTES) FOR MUL/DIV.
134 | 1 UniFP.asm 134 | Code | 11 | | 2 | 00/03C1 : 86 FB | STX {$FB}
135 | 1 UniFP.asm 135 | Code | 11 | | 2 | 00/03C3 : B0 0D | BCS OVCHK ;IF CALC. SET CARRY,CHECK FOR OVFL
136 | 1 UniFP.asm 136 | Code | 11 | | 2 | 00/03C5 : 30 04 | BMI MD3 ;IF NEG THEN NO UNDERFLOW.
137 | 1 UniFP.asm 137 | Code | 11 | | 1 | 00/03C7 : 68 | PLA ;POP ONE RETURN LEVEL.
138 | 1 UniFP.asm 138 | Code | 11 | | 1 | 00/03C8 : 68 | PLA
139 | 1 UniFP.asm 139 | Code | 11 | | 2 | 00/03C9 : 90 B2 | BCC NORMX ;CLEAR X1 AND RETURN.
140 | 1 UniFP.asm 140 | Code | 11 | | 2 | 00/03CB : 49 80 | MD3 EOR #$80 ;COMPLEMENT SIGN BIT OF EXPONENT.
141 | 1 UniFP.asm 141 | Code | 11 | | 2 | 00/03CD : 85 FA | STA {$FA} ;STORE IT.
142 | 1 UniFP.asm 142 | Code | 11 | | 2 | 00/03CF : A0 17 | LDY #$17 ;COUNT 24 MUL/23 DIV ITERATIONS.
143 | 1 UniFP.asm 143 | Code | 11 | | 1 | 00/03D1 : 60 | RTS ;RETURN.
144 | 1 UniFP.asm 144 | Code | 11 | | 2 | 00/03D2 : 10 F7 | OVCHK BPL MD3 ;IF POSITIVE EXP THEN NO OVFL.
145 | 1 UniFP.asm 145 | Code | 11 | | 3 | 00/03D4 : 4C F5 03 | OVFL JMP {$3F5}
146 | 1 UniFP.asm 146 | Comment | 11 | | 0 | 00/03D7 | * ORG $F63D
147 | 1 UniFP.asm 147 | Code | 11 | | 3 | 00/03D7 : 20 58 03 | FIX1 JSR RTAR
148 | 1 UniFP.asm 148 | Code | 11 | | 2 | 00/03DA : A5 FA | FIX LDA {$FA} ; <------------------------------ fp to int
149 | 1 UniFP.asm 149 | Code | 11 | | 2 | 00/03DC : 10 13 | BPL UNDFL
150 | 1 UniFP.asm 150 | Code | 11 | | 2 | 00/03DE : C9 8E | CMP #$8E
151 | 1 UniFP.asm 151 | Code | 11 | | 2 | 00/03E0 : D0 F5 | BNE FIX1
152 | 1 UniFP.asm 152 | Code | 11 | | 2 | 00/03E2 : 24 FB | BIT {$FB}
153 | 1 UniFP.asm 153 | Code | 11 | | 2 | 00/03E4 : 10 0A | BPL FIXRTS
154 | 1 UniFP.asm 154 | Code | 11 | | 2 | 00/03E6 : A5 FD | LDA {$FB}+2
155 | 1 UniFP.asm 155 | Code | 11 | | 2 | 00/03E8 : F0 06 | BEQ FIXRTS
156 | 1 UniFP.asm 156 | Code | 11 | | 2 | 00/03EA : E6 FC | INC {$FB}+1
157 | 1 UniFP.asm 157 | Code | 11 | | 2 | 00/03EC : D0 02 | BNE FIXRTS
158 | 1 UniFP.asm 158 | Code | 11 | | 2 | 00/03EE : E6 FB | INC {$FB}
159 | 1 UniFP.asm 159 | Code | 11 | | 1 | 00/03F0 : 60 | FIXRTS RTS
160 | 1 UniFP.asm 160 | Code | 11 | | 2 | 00/03F1 : A9 00 | UNDFL LDA #$0
161 | 1 UniFP.asm 161 | Code | 11 | | 2 | 00/03F3 : 85 FB | STA {$FB}
162 | 1 UniFP.asm 162 | Code | 11 | | 2 | 00/03F5 : 85 FC | STA {$FB}+1
163 | 1 UniFP.asm 163 | Code | 11 | | 1 | 00/03F7 : 60 | RTS
------+---------------------+-------------+----+---------+------+-----------------------+-------------------------------------------------------------------

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*
* Unidisk 3.5 Driver <alfa>
*
* The target of this project is to use the Unidisk 3.5 driveto perform
* specific numerical routines (integers and floating point numbers)
* calculation in order to use it as a Apple II co-processor unit.
*
* Copyright (C) 2015 Riccardo Greco <rigreco.grc@gmail.com>.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*
* @com.wudsn.ide.asm.hardware=APPLE2
*
* Protocol Converter Call
XC
ZPTempL equ $0006 ;Temporary zero page storage
ZPTempH equ $0007
** Zero page storage **
N1 equ $FA ;25 4 Byte FP FA--FD (FP1)
N2 equ $EC ;27 4 Byte FP EC--EF (FP2)
; RSLT equ $1D ;29
*** Monitor routines ***
COut equ $FDED ;Console output ASCII
CROut equ $FD8E ;Carriage return
** Command Code **
StatusCmd equ 0
** Status Code **
* StatusDIB equ 3
StatusUNI equ 5
*
ControlCmd equ 4
** Control Codes **
Eject equ 4
Run equ 5
SetDWLoad equ 6
DWLoad equ 7
*
org $8000
*****************************************************
*
* Find a Protocol Converter in one of the slots.
START jsr FindPC
bcs Error
*** Eject ***
jsr Dispatch
dfb ControlCmd
dw E_JECT
*** Set Address ***
jsr Dispatch
dfb ControlCmd
dw SET_ADD
*
jsr EXEC ; Jump the Error routine
rts
*********************************************
Error equ *
*
* There's either no PC around, or there was no give message
*
ldx #0
err1 equ *
lda Message,x
beq errout
jsr COut
inx
bne err1
*
errout equ *
rts
*
Message asc 'NO PC OR NO DEVICE'
dfb $8D,0
*********************************************
*
** Set the Input Value first in Dynamic data **
** 4 Byte N1 to FP1 **
EXEC lda N1 ;X1
sta $8111 ; Absolute addressing
lda N1+1 ;M1 (1)
sta $8112
lda N1+2 ;M1 (2)
sta
lda N1+2 ;M1 (3)
sta
** 4 Byte N2 to FP2 **
lda N2 ;X2
sta $80EB
lda N2+1 ;M2 (1)
sta $80EC
lda N2+2 ;M2 (2)
sta
lda N2+2 ;M2 (3)
sta
*** Download ***
jsr Dispatch
dfb ControlCmd
dw DOWNLOAD
** Set Unidisk Registers **
lda #01 ;First time
sta UNIAcc_reg
** Execute **
jsr Dispatch
dfb ControlCmd
dw EXE
** Read **
READ jsr Dispatch
dfb StatusCmd
dw DParms
bcs Error
*
**** Store Output results in //c ****
* First time execute *
lda UNIAcc_reg
sta N1
lda UNIX_reg
sta N1+1 ; Store the result
lda UNIY_reg
sta N1+2
** Second time execute **
lda #02 ; Second time
sta UNIAcc_reg
** Execute **
jsr Dispatch
dfb ControlCmd
dw EXE
** Read **
jsr Dispatch
dfb StatusCmd
dw DParms
bcs Error
* Second time execute only to read the latest Byte of FP1*
lda UNIAcc_reg
sta N1+2
*
rts
******************************************************
FindPC equ *
*
* Search slot 7 to slot 1 looking for signature bytes
*
ldx #7 ;Do for seven slots
lda #$C7
sta ZPTempH
lda #$00
sta ZPTempL
*
newslot equ *
ldy #7
*
again equ *
lda (ZPTempL),y
cmp sigtab,y ;One for byte signature
beq maybe ;Found one signature byte
dec ZPTempH
dex
bne newslot
*
* if we get here, no PC find
sec
rts
*
* if we get here, no byte find on PC
maybe equ *
dey
dey ;if N=1 then all sig bytes OK
bpl again
* Found PC interface. Set up call address.
* we already have high byte ($CN), we need low byte
*
foundPC equ *
lda #$FF
sta ZPTempL
ldy #0 ;For indirect load
lda (ZPTempL),y ;Get the byte
*
* Now the Acc has the low oreder ProDOS entry point.
* The PC entry is three locations past this ...
*
clc
adc #3
sta ZPTempL
*
* Now ZPTempL has PC entry point.
* Return with carry clear.
*
clc
rts
***********************************************************
*
* There are the PC signature bytes in their relative order.
* The $FF bytes are filler bytes and are not compared.
*
sigtab dfb $FF,$20,$FF,$00
dfb $FF,$03,$FF,$00
*
Dispatch equ *
jmp (ZPTempL) ;Simulate an indirect JSR to PC
*
*** Status Parameter Set for UNI ***
DParms equ *
DPParmsCt dfb 3 ;Status calls have three parameters
DPUnit dfb 1
DPBuffer dw UNI
DPStatCode dfb StatusUNI
*
*
*
*** Status List UNI ***
UNI equ *
dfb 0
UNIError dfb 0
UNIRetries dfb 0
UNIAcc_reg dfb 0
UNIX_reg dfb 0
UNIY_reg dfb 0
UNIP_val dfb 0
HHH dfb 0
*
*** Set Address ***
SET_ADD equ *
dfb 3
dfb 1
dw CNTL_LIST3
dfb SetDWLoad
*
*** Download ***
DOWNLOAD equ *
dfb 3
dfb 1
dw CNTL_LIST4
dfb DWLoad
*
*** Execute ***
EXE equ *
dfb 3
dfb 1
dw CNTL_LIST2
dfb Run
*** Eject ***
E_JECT equ *
dfb 3
dfb 1
dw CNTL_LIST1
dfb Eject
*
******** CONTROL LISTS ********
*
*
*** Eject ***
CNTL_LIST1 equ *
dw $0000
*
*** Execute ***
CNTL_LIST2 equ *
Clow_byte dfb $06
Chigh_byte dfb $00
AccValue dfb $00 ; Input Value
X_reg dfb $00 ; Input Value (N1)
Y_reg dfb $00 ; Input Value (N2)
ProStatus dfb $00 ; Input Value
LowPC_reg dfb $05 ; Like ORG
HighPC_reg dfb $05
*
*** Set Address ***
CNTL_LIST3 equ *
CountL_byte dfb $02
CountH_byte dfb $00
LByte_Addr dfb $05 ; Like ORG
HByte_Addr dfb $05
*
*** Download ***
CNTL_LIST4 equ *
LenghtL_byte dfb $4A ;<----- Lenght of Unidisk program Lo Byte
LenghtH_byte dfb $00 ;<----- Lenght of Unidisk program Hi Byte
*
*** Start UNIDISK Program ***
org $0505
SIGN EQU $C0 ;$EB ; $F3
** FP2 4 Bytes **
X2 EQU $C1 ;$EC ; $F4
M2 EQU $C2 ;$ED ; $F5 - $F7
** FP1 4 Bytes + E extension **
X1 EQU $C5 ;$FA ; $F8
M1 EQU $C6 ;$FB ; $F9 - $FB
E EQU $C9 ;$FE ; $FC
OVLOC EQU $C10 ;$3F5 ;Overflow routine is not implemented at now)
*
** Main program **
*
* CHK if is the second execution *
cmp #02
beq SECOND
** Input data to Zero Page **
** FP1 **
lda FP1
sta X1
lda FP1+1
sta M1
lda FP1+2
sta M1+1
lda FP1+3
sta M1+2
** FP2 **
lda FP2
sta X2
lda FP2+1
sta M2
lda FP2+2
sta M2+1
lda FP2+3
sta M2+2
*** Target Function ***
* Y=N1+N2
** Simple ADD **
jsr FADD
*** Output Data result FP1 to Unidisk registers First Time first 3 Byte***
lda X1
ldx M1
ldy M1+1
rts
*** Output Data result FP1 to Unidisk registers Second Time latest 1 Byte***
SECOND lda M1+2
rts
** FP Routine **
*
***********************
* *
* APPLE-II FLOATING *
* POINT ROUTINES *
* *
* COPYRIGHT 1977 BY *
* APPLE COMPUTER INC. *
* *
* ALL RIGHTS RESERVED *
* *
* S. WOZNIAK *
* *
***********************
* TITLE "FLOATING POINT ROUTINES for Unidisk memory"
*
* ORG $300
ADD CLC ;CLEAR CARRY
LDX #$2 ;INDEX FOR 3-BYTE ADD.
ADD1 LDA M1,X
ADC M2,X ;ADD A BYTE OF MANT2 TO MANT1
STA M1,X
DEX ;INDEX TO NEXT MORE SIGNIF. BYTE.
BPL ADD1 ;LOOP UNTIL DONE.
RTS ;RETURN
MD1 ASL SIGN ;CLEAR LSB OF SIGN.
JSR ABSWAP ;ABS VAL OF M1, THEN SWAP WITH M2
ABSWAP BIT M1 ;MANT1 NEGATIVE?
BPL ABSWAP1 ;NO, SWAP WITH MANT2 AND RETURN.
JSR FCOMPL ;YES, COMPLEMENT IT.
INC SIGN ;INCR SIGN, COMPLEMENTING LSB.
ABSWAP1 SEC ;SET CARRY FOR RETURN TO MUL/DIV.
SWAP LDX #$4 ;INDEX FOR 4 BYTE SWAP.
SWAP1 STY E-1,X
LDA X1-1,X ;SWAP A BYTE OF EXP/MANT1 WITH
LDY X2-1,X ;EXP/MANT2 AND LEAVE A COPY OF
STY X1-1,X ;MANT1 IN E (3 BYTES). E+3 USED
STA X2-1,X
DEX ;ADVANCE INDEX TO NEXT BYTE
BNE SWAP1 ;LOOP UNTIL DONE.
RTS ;RETURN
FLOAT LDA #$8E ;INIT EXP1 TO 14, <--------------- int to fp
STA X1 ;THEN NORMALIZE TO FLOAT.
NORM1 LDA M1 ;HIGH-ORDER MANT1 BYTE.
CMP #$C0 ;UPPER TWO BITS UNEQUAL?
BMI RTS1 ;YES, RETURN WITH MANT1 NORMALIZED
DEC X1 ;DECREMENT EXP1.
ASL M1+2
ROL M1+1 ;SHIFT MANT1 (3 BYTES) LEFT.
ROL M1
NORM LDA X1 ;EXP1 ZERO?
BNE NORM1 ;NO, CONTINUE NORMALIZING.
RTS1 RTS ;RETURN.
FSUB JSR FCOMPL ;CMPL MANT1,CLEARS CARRY UNLESS 0 <---- sub
SWPALGN JSR ALGNSWP ;RIGHT SHIFT MANT1 OR SWAP WITH
FADD LDA X2 ;<------------------------------------- add
CMP X1 ;COMPARE EXP1 WITH EXP2.
BNE SWPALGN ;IF #,SWAP ADDENDS OR ALIGN MANTS.
JSR ADD ;ADD ALIGNED MANTISSAS.
ADDEND BVC NORM ;NO OVERFLOW, NORMALIZE RESULT.
BVS RTLOG ;OV: SHIFT M1 RIGHT, CARRY INTO SIGN
ALGNSWP BCC SWAP ;SWAP IF CARRY CLEAR,
* ELSE SHIFT RIGHT ARITH.
RTAR LDA M1 ;SIGN OF MANT1 INTO CARRY FOR
ASL ;RIGHT ARITH SHIFT.
RTLOG INC X1 ;INCR X1 TO ADJUST FOR RIGHT SHIFT
BEQ OVFL ;EXP1 OUT OF RANGE.
RTLOG1 LDX #$FA ;INDEX FOR 6:BYTE RIGHT SHIFT.
ROR1 ROR E+3,X
INX ;NEXT BYTE OF SHIFT.
BNE ROR1 ;LOOP UNTIL DONE.
RTS ;RETURN.
FMUL JSR MD1 ;ABS VAL OF MANT1, MANT2 <-------------- mul
ADC X1 ;ADD EXP1 TO EXP2 FOR PRODUCT EXP
JSR MD2 ;CHECK PROD. EXP AND PREP. FOR MUL
CLC ;CLEAR CARRY FOR FIRST BIT.
MUL1 JSR RTLOG1 ;M1 AND E RIGHT (PROD AND MPLIER)
BCC MUL2 ;IF CARRY CLEAR, SKIP PARTIAL PROD
JSR ADD ;ADD MULTIPLICAND TO PRODUCT.
MUL2 DEY ;NEXT MUL ITERATION.
BPL MUL1 ;LOOP UNTIL DONE.
MDEND LSR SIGN ;TEST SIGN LSB.
NORMX BCC NORM ;IF EVEN,NORMALIZE PROD,ELSE COMP
FCOMPL SEC ;SET CARRY FOR SUBTRACT. <--------------- not
LDX #$3 ;INDEX FOR 3 BYTE SUBTRACT.
COMPL1 LDA #$0 ;CLEAR A.
SBC X1,X ;SUBTRACT BYTE OF EXP1.
STA X1,X ;RESTORE IT.
DEX ;NEXT MORE SIGNIFICANT BYTE.
BNE COMPL1 ;LOOP UNTIL DONE.
BEQ ADDEND ;NORMALIZE (OR SHIFT RT IF OVFL).
FDIV JSR MD1 ;TAKE ABS VAL OF MANT1, MANT2. <--------- div
SBC X1 ;SUBTRACT EXP1 FROM EXP2.
JSR MD2 ;SAVE AS QUOTIENT EXP.
DIV1 SEC ;SET CARRY FOR SUBTRACT.
LDX #$2 ;INDEX FOR 3-BYTE SUBTRACTION.
DIV2 LDA M2,X
SBC E,X ;SUBTRACT A BYTE OF E FROM MANT2.
PHA ;SAVE ON STACK.
DEX ;NEXT MORE SIGNIFICANT BYTE.
BPL DIV2 ;LOOP UNTIL DONE.
LDX #$FD ;INDEX FOR 3-BYTE CONDITIONAL MOVE
DIV3 PLA ;PULL BYTE OF DIFFERENCE OFF STACK
BCC DIV4 ;IF M2<E THEN DON'T RESTORE M2.
STA M2+3,X
DIV4 INX ;NEXT LESS SIGNIFICANT BYTE.
BNE DIV3 ;LOOP UNTIL DONE.
ROL M1+2
ROL M1+1 ;ROLL QUOTIENT LEFT, CARRY INTO LSB
ROL M1
ASL M2+2
ROL M2+1 ;SHIFT DIVIDEND LEFT
ROL M2
BCS OVFL ;OVFL IS DUE TO UNNORMED DIVISOR
DEY ;NEXT DIVIDE ITERATION.
BNE DIV1 ;LOOP UNTIL DONE 23 ITERATIONS.
BEQ MDEND ;NORM. QUOTIENT AND CORRECT SIGN.
MD2 STX M1+2
STX M1+1 ;CLEAR MANT1 (3 BYTES) FOR MUL/DIV.
STX M1
BCS OVCHK ;IF CALC. SET CARRY,CHECK FOR OVFL
BMI MD3 ;IF NEG THEN NO UNDERFLOW.
PLA ;POP ONE RETURN LEVEL.
PLA
BCC NORMX ;CLEAR X1 AND RETURN.
MD3 EOR #$80 ;COMPLEMENT SIGN BIT OF EXPONENT.
STA X1 ;STORE IT.
LDY #$17 ;COUNT 24 MUL/23 DIV ITERATIONS.
RTS ;RETURN.
OVCHK BPL MD3 ;IF POSITIVE EXP THEN NO OVFL.
OVFL JMP OVLOC
* ORG $F63D
FIX1 JSR RTAR
FIX LDA X1 ; <------------------------------ fp to int
BPL UNDFL
CMP #$8E
BNE FIX1
BIT M1
BPL FIXRTS
LDA M1+2
BEQ FIXRTS
INC M1+1
BNE FIXRTS
INC M1
FIXRTS RTS
UNDFL LDA #$0
STA M1
STA M1+1
RTS
** Input Dynamic Data append in the end of Unidisk routine **
FP1 dfb $00
dfb $00
dfb $00
dfb $00
*
FP2 dfb $00
dfb $00
dfb $00
dfb $00