Danny Decell wrote:
> 1) Where does the file hos.inc actually reside? I must be blind because
> I couldn't find it in the extracted files and folders provided when I
> downloaded the whole package.

I use a different naming convention for files so that the build system can
automatically identify them.  All regular PIC assembler source file names
end in .aspic.  The file you are looking for is called HOS.INS.ASPIC and is
in the SOURCE/PICS directory.  All the ASPIC files are translated to the
native MPASM files by the preprocessor.

> 2) When I do find hos.inc is that where the actual hard coded values for
> w_save and status_save are when you take your interrupt?

No, these are local variables in HOS_INTR.ASPIC.  They are only used during
interrupts, so there is no need to make them visible outside the interrupt
module.  That's one of the nice things about using the linker and having
multiple source modules.

The addresses of W_SAVE and STATUS_SAVE are not hard coded.  The source code
defines the linker section they must be allocated from, but the linker
decides the exact address.  There is no reason the source code needs them to
be at a particular address within their sections (that's why the sections
are defined as they are).

> I am
> interested in seeing where you save these values and how you guard
> context when the data bank is somewhere other than bank zero at the
> time of an interrupt.

The code is in HOS_INTR.ASPIC.  W is saved into global (unbanked RAM) so
that the bank settings at the time of the interrupt don't matter.  STATUS is
saved into bank 0, but the value is written to STATUS_SAVE only after a CLRF
STATUS is done to ensure bank 0 is set.


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