AN3429

Code protection overview

Doc ID 019008 Rev 1

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Code protection overview

The Flash is divided into two main areas:

●

Primary application code: contains the IP memory protection code, the IP code to be

protected and the IAP code that enables the loading of the end-user application.

●

User code: contains the end-user application and uses the primary system application

API offered by the IP memory protection code to provide access to the IP code in

protected mode.

Figure 1 shows an example of Flash memory mapping (STM32F2 family)

Figure 1.

Flash memory mapping

The IP Code is starts at address 0x0801 0000 defined in the linker file as follows:

define region IP_CODE_region = mem:[from 0x08010000 size 0x10000];

place in IP_CODE_region

{ section IP_Code };

In this example the functions to be protected are forced-loaded in the IP code section using

the following pragma with IAR:

#pragma location="IP_Code"

(Function definition)

The end user project uses the exported_api.h file that contains the IP code APIs of the

function used by the end user application.