ST STM32H7R3 Application Note

Getting started with debug authentication (DA) for STM32 MCUs
Introduction
This document describes the debug authentication (DA) security service. When not specified, STM32 refers to all applicable
products present in Table 1. Applicable
The STM32 debug authentication controls the product life cycle, such as regressions (for more details about the life cycle, refer
to the reference manual), and debug reopening:
• Regression
The user leverages the regression service to erase the user firmware and data within the user flash memory, SRAM, and
option-byte keys (OBK) when OBK are supported by STM32. After a regression, STM32 falls back in product state open.
Depending on STM32 products, there can be several kinds of regression: full regression and partial regression Refer to
Section 3: STM32 debug authentication services description
• Debug reopening
The user leverages the debug reopening to safely reopen the debug on STM32 when it is in a product state different than
open.
When the STM32 product state is not open, the user can trigger the debug authentication services by sending a password or a
certificate chain to the STM32 device.
These two options are named the debug authentication methods.
The debug authentication protocol uses the STM32 device debug access port 0 (DAP0) and the DBGMCU IP for
communication.
The STM32 debug authentication implements the Arm
®
The Arm PSA ADAC protocol is based on the certificate chain and the challenge/response principle.
Type
Microcontrollers
AN6008 - Rev 2 - May 2024
For further information contact your local STMicroelectronics sales office.
products.
Figure 1. Debug authentication interface
Debug port
Probe
/ DBGMCU
®
PSA ADAC (authenticated debug access control) specification.
Table 1. Applicable products
STM32H5 series, STM32H7R3/7S3, STM32H7R7/7S7 lines
for more details.
STM32
Debug
Authentication
Product
AN6008
Application note
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