>> =A0 =A0overlay uint8_t *inBufPtr;
>> =A0 =A0overlay uint8_t bitIn =3D startBit;
>> =A0 =A0overlay uint8_t bitOut =3D 0;
>> =A0 =A0overlay uint8_t outIndex =3D 0;
>
> Is this the equivalent of a Union?
>


No. See section 2.3.1 of the C18 User Guide:

"The MPLAB C18 compiler introduces a storage class of overlay. The overlay
storage class applies only when the compiler is operating in
Non-Extended mode (see
Section 1.2.5 =93Selecting the Mode=94). The overlay storage class may be a=
pplied to
local variables (but not formal parameters, function definitions or
global variables). The
overlay storage class will allocate the associated symbols into a
function-specific,
static overlay section. Such a variable will be allocated statically,
but initialized upon
each function entry.
...
The advantage of using overlay locals is that they are statically
allocated, which means
that, in general, fewer instructions are required to access them
(resulting in a smaller
program memory image). At the same time, the total data memory
allocation required
for these variables may be less than what would be required had they
been declared
as static due to the fact that some of the variables may be overlaid."

-Scott

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