Hi folks,
    I'm with problems when doing a "computed goto" with a PIC18F4680.

    I've debugged a lot of times and I don't know what's happening.

    I did a sample program to illustrate my problem:

The code below works fine because the "computed goto" program area don't =

change the PCLATH value. PCLATH always is zero.

-----------------------------------------------------------------------
PROGRAM   CODE 0x0030
Program:
goto Main


ANOTHER_AREA CODE 0x80
Main:
 movlw .2
 addwf PCL
 goto Main0
 goto Main2
 goto Main4

Main0:
 nop
 goto Main

Main2:
 nop
 goto Main

Main4:
 nop
 goto Main4
--------------------------------------------------------------------------

However, IF the Main routine is in 0x100 program memory area (or 0x200, =

0x300, and so on), the problem happens and after the addwf a jump to a 0x0n=
n =

area is performed.

THIS CODE DOESN'T =

WORKS----------------------------------------------------------------------=
----------------------------------------
PROGRAM   CODE 0x0030
blProgram:
 goto Main


ANOTHER_AREA CODE 0x100
Main:
 movlw .2
 addwf PCL
 goto Main0
 goto Main2
 goto Main4

Main0:
 nop
 goto Main

Main2:
 nop
 goto Main

Main4:
 nop
 goto Main4
---------------------------------------------------------------------------=
-----------------------------------------------------------------------


I see in simulator that PCLATH value never is changed. So, when I use ADDWF =

PCL, the program jumps to a 0nn relative area insted 1nn.

"goto" shouldn't change the complete program counter?

Anybody know what I'm doing wrong??

Sorry my bad english but I hope you understood me.

Thanks,
Eduardo Garcia





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