You could write a function or macro to do this.
Use a char array as the underlying type and abstract the bit access in
the function/macro:

Ex.:
void SetBit( char *v, int n )
    {
    v[n>>3] |=3D 1 << ( n & 7 );
    }

void ClrBit( char *v, int n )
    {
    v[n>>3] &=3D ~( 1 << ( n & 7 ));
    }

int ReadBit( char *v, int n )
    {
    return ( v[n>>3] & ( 1 << ( n & 7 ))) ? 1 : 0;
    }

Justin Richards escreveu:
> was tagged [tech]
>
> 2009/7/21 Justin Richards <justin.richards@gmail.com>
>
>   =

>> In C18 a union can be described as follows
>>
>> typedef union _IP_ADDR
>> {
>>     BYTE        v[4];
>>     DWORD       Val;
>> } IP_ADDR;
>>
>>
>> Then memory may be referenced as follows [after a variable IP of type
>> IP_ADDR is declared]
>> i=3D3;
>> IP.v[i];
>>
>> Can a similar member reference be used with bits.
>>
>> That is instead of referencing a bit member in the union below as
>>
>> iomask.bits.b0;
>>
>> Can it be referenced as
>>
>> iomask.bits[i]; or perhaps iomask.bits.b[i];
>>
>> Experimenting with the compiler seems to indicate that it is not possibl=
e.
>>
>> Pointers to examples etc would be greatly appreciated or even what to
>> google for.
>>
>>       union
>>         {
>>             struct
>>             {
>>                 unsigned char b0:1;
>>                 unsigned char b1:1;
>>                 unsigned char b2:1;
>>                 unsigned char b3:1;
>>                 unsigned char b4:1;
>>                 unsigned char b5:1;
>>                 unsigned char b6:1;
>>                 unsigned char b7:1;
>>             } bits;
>>             BYTE val;
>>         } iomask;
>>
>> Cheers Justin
>>
>>
>>
>>     =

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>>
>>
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