Forums

Required memory estimation.

Started by JY Kim April 25, 2007
I need to pre-estimate required memory of our project
I have experience in device driver programming of PocketPC but I have
never done things like this before
I am using ST STR7 32bit arm7 mcu without OS, but our final goal is
using OS my company has developed.
I think currently only method by which I can assume required memory is
just counting byte.
Then what I add to estimate required memory? size of device drivers
and kernel and UI and what other things?
and as for deivce driver, Can I just add size of object code that arm
compiler compiled? Just I have said above. I am not currently using
OS, but I have to use later.
And how about the size of RAM?
It seems that big wall is in front of me for this assignment.
Please answer me anythig you know about this matter.
Thanks.

JY Kim wrote:
> I need to pre-estimate required memory of our project
"Pre-estimate" is redundant. The word you want is "estimate".
> I have experience in device driver programming of PocketPC but I have > never done things like this before > I am using ST STR7 32bit arm7 mcu without OS, but our final goal is > using OS my company has developed. > I think currently only method by which I can assume required memory is > just counting byte.
The place to start is usually to find the code space used by similar applications.
> Then what I add to estimate required memory? size of device drivers > and kernel and UI and what other things?
Whatever you application will contain. We don't know that. For data storage, you can use a combination of utilization by similar applications and analysis. It is wise to allow a significant amount of spare memory for two reasons: 1) uncertainty of your estimate 2) future growth of the code when features are added. Running up against implementation limits, such as the amount of available code space tends to substantially increase the amount of time adapting your solution to the limitations. For a project with a number of unknowns it is better to get more than enough resources. After the project is complete you can assess the amount of unneeded resources and design the production version to eliminate them, if desired. -- Thad
JY Kim wrote:

Can I just add size of object code that arm
> compiler compiled? Just I have said above. I am not currently using > OS, but I have to use later. > And how about the size of RAM? > It seems that big wall is in front of me for this assignment. > Please answer me anythig you know about this matter. > Thanks.
Hi , I assume you are using the Arm toolchain. If you have compiled your code and got a Map file. At the end of the map file there is a summary. Explore the map file more which should give you the information you require. HTH, Prasanna.