array problem

[Darrel Taylor]

OH! A competition.

And as usual, I'm too late, oh well. Here's my entry.

<font color="#008000"><b>DEFINE  </b></font><b>NO_CLRWDT 1                   </b><font color="#0000FF"><b><i>; Saves 2 words  :)

</i></b></font><b>array </b><font color="#008000"><b>VAR WORD </b></font>[<b>5</b>] <b>BANK0 SYSTEM 

ArrayStart </b><font color="#008000"><b>CON </b></font><b>EXT
</b><font color="#000080">@ArrayStart = array + 1               </font><font color="#0000FF"><b><i>; Start at highbyte of element 0
</i></b></font><b>LastElement </b><font color="#008000"><b>CON </b></font><b>EXT
</b><font color="#000080">@LastElement = ArrayStart + (4 * 2)   </font><font color="#0000FF"><b><i>; Stop at element 4

</i></b></font><b>FSR </b>= <b>ArrayStart  
Loop1</b>:
    <font color="#008000"><b>IF </b></font><b>INDF </b>= <b>0 </b><font color="#008000"><b>THEN GOSUB </b></font><b>Compute
    FSR </b>= <b>FSR </b>+ <b>2
</b><font color="#008000"><b>IF </b></font><b>FSR </b>&lt; <b>LastElement </b><font color="#008000"><b>THEN </b></font><b>Loop1
</b><font color="#0000FF"><b><i>;----------------------------------

</i></b></font><b>Compute</b>:
<font color="#0000FF"><b><i>'Do something
</i></b></font><font color="#008000"><b>RETURN</b></font>

21 words<hr>
Or going the ASM route

<font color="#000000"><b>array </b><font color="#008000"><b>VAR WORD </b></font>[<b>5</b>] <b>BANK0 SYSTEM 

</b><font color="#008000"><b>ASM
</b></font><font color="#000080">ArrayStart = array + 1               </font><font color="#0000FF"><b><i>; Start at highbyte of element 0
</i></b></font><font color="#000080">LastElement = ArrayStart + (4 * 2)   </font><font color="#0000FF"><b><i>; Stop at element 4
    </i></b></font><font color="#000080">movlw    ArrayStart
    movwf    FSR                     </font><font color="#0000FF"><b><i>; FSR = ArrayStart
</i></b></font><font color="#000080">Loop1
    movf     INDF, W                
    btfsc    STATUS, Z               
    call     _Compute                </font><font color="#0000FF"><b><i>; if INDF = 0 then gosub Compute
    </i></b></font><font color="#000080">movlw    2
    addwf    FSR, F                  </font><font color="#0000FF"><b><i>; FSR = FSR + 2
    </i></b></font><font color="#000080">movlw    LastElement
    subwf    FSR, W
    btfss    STATUS, C
    goto     Loop1                   </font><font color="#0000FF"><b><i>; if FSR &lt; LastElement then Loop1
</i></b></font><font color="#008000"><b>ENDASM    
</b></font><font color="#0000FF"><b><i>;----------------------------------

</i></b></font><b>Compute</b>:
<font color="#0000FF"><b><i>'Do something
</i></b></font><font color="#008000"><b>RETURN</b></font>

13 words

[mister_e]

Neat!
I wasn't aware that we could access to FSR and INDF directly... thanks!

i just hope our friend don't use 18Fs or some 12 bit core

[Darrel Taylor]

>> i just hope our friend don't use 18Fs or some 12 bit core

I had the same concerns, but after compiling the "Melanie idea for solution" example(post 9), I found that it was 35 words instead of bytes. So I knew he was using a 16F (or C).

And yup, you can directly access any register with PBP. They are all defined in the PIC14EXT.BAS file in the PBP folder.
<br>