Hi all,

I'm trying to define a status register in XC8. I'd like to be able to
reference individual bits, but also be able to say, clear the variable
as a whole.

I currently have it defined as this:

typedef union {
        struct
        {
            unsigned ENC1UP                    :1;
            unsigned ENC1DN                    :1;
            unsigned ENC2UP                    :1;
            unsigned ENC2DN                    :1;
            unsigned ENC3UP                    :1;
            unsigned ENC3DN                    :1;
            unsigned ENC4UP                    :1;
            unsigned ENC4DN                    :1;
        };
        struct
        {
            unsigned                            :8;
        };

} EncStatus_t;

In another part of the code, I define a variable using the typedef EncStatu=
s_t.

In my code, I have two lines that try to write to that variable:

   EncStatus.ENC1DN =3D 1;
   EncStatus =3D 0;                  // Clear encoder status register

The first line works perfect. The second line throws an error though -
illegal conversion between types - int -> volatile union.

I understand the basic problem here, but I can't seem to fix it. I've
spent a bunch of time looking at the header file for my processor, to
see how I can write to both PORTB and PORTBbits.RB0 successfully. Near
as I can tell, it's because both of those variables are explicitly
being declared at the same address, not because there's anything fancy
in the union.

So...is there a way to deal with this when I don't know where the
variable will be assigned?

To be clear, this isn't a work stopping problem, I'd just like to know
if there's a way to do this that is efficient. After all, I can always
just clear each bit individually.

Thanks!

Josh
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