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Peripheral migration guide

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Peripheral migration guide

2.1

STM32 product cross-compatibility

The STM32 microcontrollers embed a set of peripherals that can be classed in three

categories:

1.

Peripherals which are by definition common to all products. Those peripherals are

identical, so they have the same structure, registers and control bits. There is no need

to perform any firmware change to keep the same functionality at the application level

after migration. All the features and behavior remain the same.

2.

Peripherals which are shared by all products but have only minor differences (in

general to support new features), so migration from one product to another is very easy

and does not need any significant new development effort.

3.

Peripherals which have been considerably changed from one product to another (new

architecture, new features...). For this category of peripherals, migration will require

new development at application level.

Table 3 summarizes the available peripherals and their compatibility between the

STM32F429/439 and the STM32F446 lines.

Table 3. Peripheral compatibility analysis

Peripherals

STM32F429xx/439xx STM32F446xx

Compatibility

SW

Comments

Flash memory (in Bytes)

2M

512K

-

-

SRAM

(in KBytes)

System

256

(112+16+64+64)

128

(112+16)

--

Backup

4

4

-

-

Timers

General Purpose

10

10

-

-

Advanced control

2

2

-

-

Basic

2

2

-

-