Flash Program Memory; Introduction; Main Features; Structure - STMicroelectronics ST72361 Auto Series Manual

Flash program memory

3 Flash program memory
3.1

Introduction

The ST7 dual voltage High Density Flash (HDFlash) is a non-volatile memory that can be
electrically erased as a single block or by individual sectors and programmed on a Byte-by-
Byte basis using an external V
The HDFlash devices can be programmed and erased off-board (plugged in a programming
tool) or on-board using ICP (In-Circuit Programming) or IAP (In-Application Programming).
The array matrix organization allows each sector to be erased and reprogrammed without
affecting other sectors.
3.2

Main features

●
3 Flash programming modes:
–
–
–
●
ICT (In-Circuit Testing) for downloading and executing user application test patterns in
RAM
● Read-out protection
●
Register Access Security System (RASS) to prevent accidental programming or
erasing
3.3

Structure

The Flash memory is organized in sectors and can be used for both code and data storage.
Depending on the overall Flash memory size in the microcontroller device, there are up to
three user sectors (see
avoid unnecessary erasing of the whole Flash memory when only a partial erasing is
required.
The first two sectors have a fixed size of 4 Kbytes (see
upper part of the ST7 addressing space so the reset and interrupt vectors are located in
Sector 0 (F000h-FFFFh).
Table 5.
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Insertion in a programming tool. In this mode, all sectors including option bytes
can be programmed or erased.
ICP (In-Circuit Programming). In this mode, all sectors including option bytes can
be programmed or erased without removing the device from the application board.
IAP (In-Application Programming) In this mode, all sectors except Sector 0, can be
programmed or erased without removing the device from the application board
and while the application is running.
Table 5). Each of these sectors can be erased independently to
Sectors available in Flash devices
Flash size (bytes)
4K
8K
> 8K
Doc ID 12468 Rev 3
supply.
ST72361xx-Auto
Figure 6). They are mapped in the
Available sectors
Sector 0
Sectors 0,1
Sectors 0,1, 2