Hi Mahmood,

Most compilers for the 8052 have a caveat somewhere telling how inefficient bitfields are implemented. You also have to watch out for the "implementation dependent" stuff...packing and ordering. You might have to change your code if you happened to change your compiler.

I personally would store the message in an unsigned long, and mask and shift to get the different fields. Unless you implement your own 3-byte "medium" data type, you'll have to use a long for the address anyway.

Yeah, I know it's ugly. The price you pay for using a 8 bit micro...

Dennis