It works with positive and negative vlues, some rounding.

AppleII/FP converter/Conv.asm

@@ -0,0 +1,111 @@
+* @com.wudsn.ide.asm.hardware=APPLE2
+************************************
+* 	BASIC TO FAC TO FP1        *
+*          X=NUMBER		   *
+*          CALL 768,X             *
+************************************
+		org $300
+		
+CHKCOM		equ $DEBE
+FRMNUM		equ $DD67
+PTRGET		equ $DFE3
+MOVMF		equ $EB2B
+MOVFM		equ $EAF9
+
+** Woz FP Accumulator 4 Byte + 1 Byte Extra + 1 Byte SIGN**
+FP1		equ $FA	;Translate F8 --> FA
+E		equ $FE ;Translate FC --> FE
+SIGN		equ $EB
+
+** Applesoft FP Accumulator 5 Byte + 1 Byte Sign **
+FAC		equ $9D
+
+MEM		equ $0380
+
+		***************************
+
+ENTRY1		jsr CHKCOM
+		jsr FRMNUM	;VARIABLE X ->FAC
+
+** FPC to FP1 conversion (conversion not yet) **
+
+		lda FAC
+		dec A
+		sta FP1
+		
+		clc
+		lda FAC+5
+		ror
+		sta FP1+1
+		
+		;clc
+		;lda FAC+1
+		;ror
+		;sta FP1+1
+		
+		lda FAC+2
+		;ror
+		sta FP1+2
+		
+		lda FAC+3
+		;ror
+		sta FP1+3
+		
+;		lda #0
+;		ror
+;		sta E
+		
+		lda FAC+4
+		;ror
+		sta E
+	
+		
+		rts
+		
+************************************
+* 	FP1 TO FAC TO BASIC        *
+*          CALL 798,Y      	   *
+*	   PRINT Y		   *
+************************************
+
+*
+		** FP1 to MEM to FAC conversion FAC 5 Bytes **
+*
+ENTRY2		lda FP1		; X1 1 Byte --> 9D FAC
+		inc A		; 2^(FP1+1)
+		sta MEM
+		
+		clc
+		lda FP1+1	; M1 Hi 2 Byte --> 9E FAC
+		rol
+		;asl
+		;eor #$80	; Not Hi Bit Mantissa (change Sign)
+		sta MEM+1
+		
+		lda FP1+2	; M1 3 Byte --> 9F FAC
+		;rol
+		sta MEM+2
+		
+		lda FP1+3	; M1 Lo 4 Byte --> A0 FAC
+		;rol
+		sta MEM+3
+		
+;		lda E		; Extra 00 5 Byte --> A1 FAC
+		lda #0
+		;rol
+		sta MEM+4
+		
+;		lda SIGN	; SIGN (F3 to EB) 6 Byte --> A2 FAC
+;		sta MEM+5
+		
+		***************************
+* 
+		ldy #$03 	;Hi Byte MEM
+		lda #$80 	;Lo Byte MEM
+		jsr MOVFM	;MEM->FAC (9D to A2)
+*
+		jsr CHKCOM
+		jsr PTRGET
+		tax
+		jsr MOVMF	;FAC->VARIABLE Y
+		rts