Overview

PM0068

6/31

Doc ID 17100 Rev 2

The Flash memory is organized as 32-bit wide memory cells that can be used for storing

both code and data constants. The Flash module is located at a specific base address in the

memory map of the microcontroller. For the base address, please refer to the related

STM32F101xF/G and STM32F103xF/G reference manual.

The information block is divided into two parts:

●

System memory is used to boot the device in System memory boot mode. The area is

reserved to STMicroelectronics and contains the boot loader which is used to

reprogram the Flash memory using the USART1 or USART2 (remapped) serial

interface. It is programmed by ST when the device is manufactured, and protected

against spurious write/erase operations. For further details please refer to AN2606.

●

Option bytes

Write operations to the main memory block and the option bytes are managed by an

embedded Flash program/erase Controller (FPEC). The high voltage needed for

program/erase operations is generated internally.

The main Flash memory can be protected against different types of unwanted access

(read/write/erase). There are two types of protection:

●

Page Write Protection

●

Read Protection

Refer to Section 2.4 on page 14 for more details.

During a write operation to the Flash memory, any attempt to read the Flash memory will

stall the bus. The read operation will proceed correctly once the write operation has

completed. This means that code or data fetches cannot be made while a write/erase

operation is ongoing.

Flash memory interface registers

FLASH_ACR

0x4002 2000 - 0x4002 2003

4

FLASH_KEYR

0x4002 2004 - 0x4002 2007

4

FLASH_OPTKEYR

0x4002 2008 - 0x4002 200B

4

FLASH_SR

0x4002 200C - 0x4002 200F

4

FLASH_CR

0x4002 2010 - 0x4002 2013

4

FLASH_AR

0x4002 2014 - 0x4002 2017

4

Reserved

0x4002 2018 - 0x4002 201B

4

FLASH_OBR

0x4002 201C - 0x4002 201F

4

FLASH_WRPR

0x4002 2020 - 0x4002 2023

4

Reserved

0x4002 2024 - 0x4002 2043

32

FLASH_KEYR2

0x4002 2044 - 0x4002 2047

4

Reserved

0x4002 2048 - 0x4002 204B

4

FLASH_SR2

0x4002 204C - 0x4002 204F

4

FLASH_CR2

0x4002 2050 - 0x4002 2053

4

FLASH_AR2

0x4002 2054 - 0x4002 2057

4

Table 1.

XL-density Flash module organization (continued)

Block

Name

Base addresses

Size (bytes)