Aahh the old 'friend' PCLATH is back ;-)
Kidding aside some minor comments:

Andy Stubbins wrote:

>pagesel <label>
>call    <label>
>;do something
>return

Yes this is not 'safe', You also need to ( as others suggested ) =

use an additional pagesel after the call but before the return to set to
current page ( calling ).

Don Hyde wrote:

>This eliminates the worst gotcha of the pagesel, which is that on a
14-bit
>machine like 16F876, your macro will expand to:
>
>        movlw   high <label>
>        movwf   PCLATH
>        call    <label>
>
Hmmm strange this, according to the data sheet YES, BUT not according to
my own testings, try it, it actually uses BSF/BCF instructions at least
on the 16F8xx Ive tried on. =

Nether the less it cannot be trusted.

>The paging and banking are without a doubt the ugliest, nastiest,
>bug-waiting-to-happen-est flaws of the PIC architecture.  A whole lot
of my
>programming time is devoted to finding and fixing or trying to avoid
those
>bugs.

Yep !!

Anyway to give some suggestions,
look at some erlier ramblings by me and others at:

http://www.piclist.com/techref/default.asp?from=3D/techref/piclist/../mic=
r
ochip/&url=3Dpages.htm

'Mine' are at the bottom and should work A-OK ( except the last L_CALL
thats redundant and originates from some 'playing around' )

SHORT_CALL      - Page0 <-> Page1 OR Page2 <-> Page3, two additional
instructions totally
LONG_CALL   - Any page <-> any page, four additional instructions
totally ( the same as two pagesel's )
PCALL       - same page call BUT with REAL warning for page crossings
+ some 'help' macros

Have fun,

/Tony



Tony K=FCbek, Flintab AB            =

=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=
=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=
=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2
E-mail: tony.kubek@flintab.com
=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=
=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2=
=B2=B2=B2=B2=B2=B2=B2=B2=B2=B2

--
http://www.piclist.com hint: To leave the PICList
mailto:piclist-unsubscribe-request@mitvma.mit.edu