Apple II User Manual
F4D7: 26 F6 ROL M2+1 SHIFT DIVIDEND LEFT
F4D9: 26 F5 ROL M2
F4DB: B0 1C BCS OVFL OVFL IS DUE TO UNNORMED DIVISOR
F4DB: B0 1C BCS OVFL OVFL IS DUE TO UNNORMED DIVISOR
F4DD: 88 DEY NEXT DIVIDE ITERATION.
F4DE: D0 DA BNE DIV1 LOOP UNTIL DONE 23 ITERATIONS.
F4DE: D0 DA BNE DIV1 LOOP UNTIL DONE 23 ITERATIONS.
F4E0: F0 BE BEQ MDEND NORM. QUOTIENT AND CORRECT SIGN.
F4E2: 86 FB MD2 STX M1+2
F4E2: 86 FB MD2 STX M1+2
F4E4: 86 FA STX M1+1 CLEAR MANT1 (3 BYTES) FOR MUL/DIV.
F4E6: 86 F9 STX M1
F4E6: 86 F9 STX M1
F4E8: B0 0D BCS OVCHK IF CALC. SET CARRY,CHECK FOR OVFL
F4EA: 30 04 BMI MD3 IF NEG THEN NO UNDERFLOW.
F4EA: 30 04 BMI MD3 IF NEG THEN NO UNDERFLOW.
F4EC: 68 PLA POP ONE RETURN LEVEL.
F4ED: 68 PLA
F4ED: 68 PLA
F4EE: 90 B2 BCC NORMX CLEAR X1 AND RETURN.
F4F0: 49 80 MD3 EOR #$80 COMPLEMENT SIGN BIT OF EXPONENT.
F4F0: 49 80 MD3 EOR #$80 COMPLEMENT SIGN BIT OF EXPONENT.
F4F2: 85 F8 STA X1 STORE IT.
F4F4: A0 17 LDY #$17 COUNT 24 MUL/23 DIV ITERATIONS.
F4F4: A0 17 LDY #$17 COUNT 24 MUL/23 DIV ITERATIONS.
F4F6: 60 RTS RETURN.
F4F7: 10 F7 OVCHK BPL MD3 IF POSITIVE EXP THEN NO OVFL.
F4F7: 10 F7 OVCHK BPL MD3 IF POSITIVE EXP THEN NO OVFL.
F4F9: 4C F5 03 OVFL JMP OVLOC
ORG $F63D
ORG $F63D
F63D: 20 7D F4 FIX1 JSR RTAR
F640: A5 F8 FIX LDA X1
F640: A5 F8 FIX LDA X1
F642: 10 13 BPL UNDFL
F644: C9 8E CMP #$8E
F644: C9 8E CMP #$8E
F646: D0 F5 BNE FIX1
F648: 24 F9 BIT M1
F648: 24 F9 BIT M1
F64A: 10 0A BPL FIXRTS
F64C: A5 FB LDA M1+2
F64C: A5 FB LDA M1+2
F64E: F0 06 BEQ FIXRTS
F650: E6 FA INC M1+1
F650: E6 FA INC M1+1
F652: D0 02 BNE FIXRTS
F654: E6 F9 INC M1
F654: E6 F9 INC M1
F656: 60 FIXRTS RTS
F657: A9 00 UNDFL LDA #$0
F657: A9 00 UNDFL LDA #$0
F659: 85 F9 STA M1
F65B: 85 FA STA M1+1
F65B: 85 FA STA M1+1
F65D: 60 RTS