Hi,

I made some changes in my code as a possible
simplify it.

Now I=B4m needing fast asm routine to divide
a 16 bits unsigned number by constant decimal 10
instead 100.

Look that I=B4m using a 16F pic series.


I tried to do that in below from Scott Dattalo
But some 16bits values dosen=B4t work.
For exemple:

0x7D0 / D10 =3D 0xC8 - OK
0x9C4 / D10 =3D 0x20 - ERR

;----------------------------------
;divby10
;Divides the unsigned integer N_hi:N_lo by the constant 10.
;
;Input
;      N_lo - Low byte of  the 16 bit dividend
;      N_hi - High     "                  "
;Output
;      R_lo - Low byte of the result
;      R_hi - High    "         "
;
; 14  words
; 149 cycles

divby10_ver3:
    CLRF    R_lo   ;Only need to clear R_lo. R_hi is cleared by =

shifting(below)
    MOVLW   13
    MOVWF   count  ;
v3_1:
    MOVLW   0xa0   ;If the high byte is greater than or equal to 0xa0,
    SUBWF   N_hi,W ;then this subtraction causes no borrow (i.e.C=3D1)
    SKPNC
    MOVWF N_hi     ;Replace N_hi with N_hi - 0xa0 if

    RLF     R_lo,F ;Shift result left one bit and
    RLF     R_hi,F ;   pick up the carry bit in the process.
    RLF     N_lo,F ;Adjust N for the next iteration.
    RLF     N_hi,F
    DECFSZ  count,F
    goto  v3_1

    RETURN


Any help

Best regards

Luis F.

-- =

http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist