10 bit struct, how to use less than 2 bytes?

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T3STY

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With the new LCD Driver I made I'm using an int data type to store 10 bits. Although, I'd like to reduce the size to only 10 bits, the ones I'm really using.
I tried to define a bit field into a struct like this:
Code: 
struct {
   unsigned DB0:1;
   unsigned DB1:1;
   unsigned DB2:1;
   unsigned DB3:1;
   unsigned DB4:1;
   unsigned DB5:1;
   unsigned DB6:1;
   unsigned DB7:1;
   unsigned RW:1;
   unsigned RS:1;
} LCD_DATA;
But standard C says it will fit into 2 bytes and it will use 2 bytes, even if I'll only be using 10 bits of 16 available.

Smart question: is there any way I can create a 10 bits struct so I won't waste 6 bits?
 

The structure looks like a collection of GPIO bits used to control a LCD. What's the purpose of mirroring it in memory?

Data objects are ususally aligned on byte boundaries for 8-Bit processors, with the exception of single bit variables that are supported by some processors.
 

I think each memory location is 1 byte wide. So, there are no nibble type memory location. 1 and 0 is also stored as a byte i.e., bit variable also takes 1 byte in memory. 0 is stored as 00000000.
 

The purpose is not making data any efficient, I only hate to waste every single bit on PICs because they have limited memory and any bit save can be a good. I was only trying to create a data type that would only use 10 bits instead of using an INT data type which is 16-bits long.

EDIT
oh.. what a shame! I thought it could fit bits in less space, but I was obviously wrong. The struct actually makes the data type even larger then... I'll avoid this way.
Thank you for your time guys
 

1 and 0 is also stored as a byte i.e., bit variable also takes 1 byte in memory. 0 is stored as 00000000.
Click to expand...
That's the basic way. As said, some compilers support single bit variables that are packed to memory. E.g. CCS int1 type.
 

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