MPU Configuration and Hard Fault Trigger During Enable The ARM Cortex-M3 Memory Protection Unit (MPU) is a critical component for ensuring memory safety and access control in embedded systems. However, enabling the MPU can sometimes lead to unexpected hard faults, especially if the configuration is incorrect or incomplete. In this scenario, the hard fault is…
Bare-Metal Code Development for ARM Cortex-A53 and Cortex-M4 in iMX8M Mini Developing bare-metal code for the iMX8M Mini, which features a dual-core ARM Cortex-A53 and a Cortex-M4, presents unique challenges, especially in avionics applications where certification and reliability are paramount. The Cortex-A53, being a high-performance application processor, and the Cortex-M4, a real-time microcontroller, require different…
ARM Cortex-M3 64-bit Division Performance Challenges The ARM Cortex-M3 is a widely used 32-bit microcontroller core that excels in embedded systems due to its balance of performance, power efficiency, and cost-effectiveness. However, one of its limitations is the lack of native support for 64-bit arithmetic operations, particularly division. When performing 64-bit division on the Cortex-M3,…
ARM Cortex-M33 BX Instruction Behavior in Secure State The ARM Cortex-M33 processor, based on the ARMv8-M architecture, introduces a robust security model that partitions code execution into Secure and Non-Secure states. This partitioning is enforced by the Memory Protection Unit (MPU) and the Security Attribution Unit (SAU), which define memory regions as Secure or Non-Secure….
ARM Cortex-M TrustZone Memory Access Vulnerabilities In ARM Cortex-M systems utilizing TrustZone technology, one of the most critical security challenges is ensuring that Non-Secure (NS) code cannot maliciously access Secure (S) memory regions. This issue arises due to the dual mapping of memory regions in both Secure and Non-Secure address spaces, which can lead to…
ARM Cortex-A9 ETB and Intel LBR: Functional Comparison and Use Cases The Intel Last Branch Recording (LBR) feature and ARM’s Embedded Trace Buffer (ETB) serve similar purposes in the context of instruction-level monitoring and debugging, but they differ significantly in implementation, capabilities, and overhead. Intel’s LBR is a hardware feature that records the most recent…
ARM Hardware Development for Hobbyists: Challenges and Opportunities Building ARM-based hardware as a serious hobbyist is a challenging yet rewarding endeavor. ARM processors, particularly Cortex-M series microcontrollers, are widely used in embedded systems due to their power efficiency, performance, and scalability. However, designing and implementing custom ARM-based hardware requires a combination of programming expertise, electronics…
ARM Cortex-M0 IT Instruction Misuse and Performance Impact The ARM Cortex-M0 processor, being a highly efficient and power-optimized microcontroller, relies heavily on the Thumb instruction set to achieve its design goals. One of the key features of the Thumb instruction set is the IT (If-Then) instruction, which allows for conditional execution of up to four…
ARM Cortex-M7 MPU Configuration and DDR Cache Attribute Challenges The ARM Cortex-M7 is a powerful microcontroller core designed for high-performance embedded applications. One of its key features is the Memory Protection Unit (MPU), which allows developers to define memory regions with specific attributes such as cacheability, shareability, and access permissions. However, configuring the MPU for…
ARM Cortex-A Series VMSAv8-64 Stage 2 Translation Regime: PA Size Implications The VMSAv8-64 architecture, used in ARM Cortex-A series processors, implements a two-stage address translation mechanism for virtualization. Stage 2 translation, managed by the hypervisor, maps Intermediate Physical Addresses (IPAs) to Physical Addresses (PAs). The Physical Address (PA) size supported by the system plays a…