Pointer / Multible Union Delcaration

[James]

Hello everyone,

I'm trying to set up a union (whatever works better) that always shows the data in my data[8] array but allows me to address the data differently depending on where it came from. That makes no sense, so for example:

If my data comes into my data[8] from spi, I know its going to be 3 bytes. But the last byte is bit mapped. So I want to be able to do some sort of

spidata.bitmapped1 = 0;
spidata.bitmapped6 = 0;
spidata.byte1 = 10;

but then later I'll be getting a message in from rs232 that will be 4 bytes, 2 8bit and 1 16bit in the middle.

rsr232data.byte1 = 255;
rsr232data.byte2 = 1000;
rsr232data.byte3 = 255;

I'd like to store all work in my data array (I'm only ever doing 1 thing at a time so I thought it would be a good idea to save space and only use 1 array).

I don't care if I address it all data.whatever or rs232data which would really point to &data. I just want to handle the data array differently depending on what it is coming in.

I tired this with stucts but had very little luck,

Is this a job for unions ?

[james]

Ok, I've decided that since I really don't like the -> thing that you use with unions and I'm probably making this all more complex then it needs to be,

How about taking my data[8] and temporarily assigning a struct to it ?

Instead of

[Neutone]

This is a simple method of direct addressing variables in a fixed packet structure. This will compile very effectively.

[JAMES!]

I can't beleive I didn't realize thats what I wanted all along!

Thank You Neutone !

One last thing tho. I did this: