Re: LCD Example Segmentation Faults

>> Scott Dattalo wrote:
>>> the code in CVS for gpsim ... it is about time for another release.
>>> But before I do that there are some things I need to fix as a
>>> result of the recent I/O port redesign.
>>
>> Hey Scott,
>>
>> Any room in your schedule for squeezing in a fix/patch/hack prior to
>> your release?
>>
>> Specifically, solving the 18F-specific bug of stepping over 2-word
>> 'CALL' instructions.
>
> David,
>
> I've got this fixed and will be checking in the change some time today.

The feature is now working for the 18f family. I also now treat skip
instructions like non-branching instructions. Here's a description of the
step-over feature:

The step over feature is designed to step over single instructions. If the
program counter is pointing at a non-branching instruction (e.g. MOVLW)
then the step over is identical to a step. If the program counter is
pointing at a branching instruction (e.g. CALL, RCALL, GOTO, BRA, etc)
then a break point will be set a break point at the following instruction
and the simulator will start running. If the program counter is pointing
at a skip instruction, then a step over is identical to a step. If a skip
instruction is skipping a 2-word instruction (e.g. skip followed by CALL
on the 16bit core), then a step over is still identical to a step. However
in this case, the step and step over may execute the 'nop' portion of the
2-word instruction; and unless you're looking at the program memory view
it's not obvious that this is the case.

Examples:

1) non-branching instructions:

Before step over:

==>  MOVLW   1
     MOVWF   temp

After step over:

     MOVLW   1
==>  MOVWF   temp


cycle counter increments by one count.

2) branching instructions:

Before step over:

==>  CALL    func
     MOVWF   temp

After step over:

     CALL    func
==>  MOVWF   temp

cycle counter increments by many counts.

3) skip instruction:

before step over:

==>  SKPZ
      CALL   func
     MOVWF   temp

After step over case 1:

     SKPZ
==>   CALL   func
     MOVWF   temp


After step over case 2 - mid range pics:

     SKPZ
      CALL   func
==>  MOVWF   temp

After step over case 2 - 16-bit core pics:

     SKPZ
==>   CALL   func     ; pointing at nop portion of call
     MOVWF   temp

Allow a few hours before CVS syncs up.
Scott