Thanks for the reply.

Let me get this straight, the actual occupied memory is provided as a value
for the ROM (13800). The flash memory contains the .hex file, which is then
decomposed into the ROM and RAM.

Is my understanding correct?

Regards,
--
Ricardo

On Fri, Jul 16, 2010 at 2:40 PM, Urs Hunkeler <[email protected]> wrote:

> Hi Ricardo,
>
> The HEX file is a text file. Every byte of the binary is written as two
> characters (human readable hex values). In addition, there are addresses,
> checksums and other programming or control information.
>
> If you don't assign any value to a variable declaration, that variable will
> get a reserved space in the RAM, but this space is not initialized. Hence
> there is nothing to do, the code "might" execute a little bit faster and
> "might" be a little bit smaller, but you have to be sure to do the right
> thing. If you assign a value to a variable at initialization, this value has
> to be stored somewhere and the variable needs to be initialized before it
> can be used. I think (please, someone correct me if I am wrong) this
> concerns only global variables, and the mote will copy part of the FLASH to
> the RAM when booting to initialize these variables (they always have exactly
> the same address in the RAM, determined at compile-time).
>
> Cheers,
> Urs
>
>
>
> On 7/16/10 2:55 PM, Ricardo . wrote:
>
>> Hello everyone,
>>
>> I'm trying to understand the relationship between ROM and RAM .hex file
>> generated in the build.
>> It has been said here  that:
>>
>>  > In words few ROM includes the code and initialized data RAM and
>>> includes
>>> > BOTH initialized and uninitialized data (note the stack That Is Not
>>> > Included).
>>>
>>
>> But for example, when compiling the code this values are displayed: ROM:
>> 13800 bytes, RAM: 594 bytes and the .hex file generated has 38 832
>> bytes. I can not see how it goes from 38832 bytes to (13800 +594) bytes.
>>
>> What is the advantage of uninitialized data in RAM?
>>
>> Someone help me understand this?
>> Regards,
>> --
>> Ricardo
>>
>
>
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