Dynamic Array substitution in composite data variable

[DavidDobson]

Hello Everyone

I have a simple packet data structure that is defined like this:

typedef struct
{
    uint8_t header; 
    uint8_t data[56];
    uint8_t footer; 
} PACK  ApplicationMessage;

The data array contains 56 bytes of payload data and when I come to send the packet I send across a variable defined from ApplicationMessage – this works very well indeed.

What I would like to do is to be able to dynamically swap out the data payload with 6 other possible arrays of data:

typedef struct
{
    uint8_t header; 
    uint8_t (***POINTER TO DATA ARRAY***)
    uint8_t footer; 
} PACK  ApplicationMessage;

Thus I could have 6 arrays:

ArrayA: 1,2,3,4,5,6,7….56
ArrayB: A,B,C,D,E,F,G…AF
ArrayC: 56, 55, 54, 53, 52…0

Etc…

And with a single command select which array is used for the ApplicationMessage variable.

Doe anyone

A) understand my ramblings
B) have any idea how to do this?

Many thanks for any assistance you can provide

FR

[rasta_freak]

So why don't you use "*data" instead of "data"? What is real problem? Allocation, switching arrays (assigning pointers), data access (sending/receiving)? Please tell more... (what exactly gives you trouble)

[DavidDobson]

Oh, well it was not a case of having problems, I just didn’t think it would be that simple…

Ill try it and report back

Thanks