I'm new to this list so I hope this makes it to the right place!

Yes you can avoid having the linker place code that straddles a page
boundary. I do this all the time. In the linker file you need to define a
codepage that is one page in length (or shorter)...

Example excert from (.LKR) linker file...

CODEPAGE   NAME=vectors   START=0x0      END=0x27     PROTECTED
CODEPAGE   NAME=page0     START=0x28     END=0xFF
CODEPAGE   NAME=page1     START=0x100    END=0x1FF    PROTECTED
CODEPAGE   NAME=page      START=0x200    END=0x0FFF
CODEPAGE   NAME=config    START=0xFE00   END=0xFE0F   PROTECTED

SECTION    NAME=JMPTBL   ROM=page1

The 3rd CODEPAGE line 'defines' an area of memory from 0x100 to 0x1FF and
gives it the name "page1"
The SECTION line tells the linker to put any code modules named JMPTBL in
page1

Then in the .ASM file you need to name the code areas like so...
JMPTBL	CODE

Then any code after the "JMPTBL CODE" directive will be placed between 0x100
and 0x1FF. Using this method gives you very good control over where the
linker puts things. If you simply start your code segments like so (without
the name )...

	CODE

	'code starts here'

Then the linker will stick the code in any unprotected codepage it finds.


Typically I have some things in a .ASM  file which I don't care about page
boundarys and some things I do care. So I write the code like so...

JMPTBL	CODE

	'Stuff that I don't want straddling a boundary (ends up at 0x100 to 0x1FF)'


		CODE

	'Other stuff that I don't care about page boundaries (ends up in one of the
unprotected codepages)'




This is covered in the MPLINK manual, but it does take some thinking about
it before it all makes sense.

I suggest you lookup the CODE directive in the MPASM manual, and also the
CODEPAGE and SECTION directives in the MPLINK manual.

Clear as mud?

-Mark


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