ARM AHB5 Protocol and HADDR Bus Width Evolution The Advanced High-performance Bus (AHB) protocol, developed by Arm, is a cornerstone of many System-on-Chip (SoC) designs, particularly in embedded systems. AHB is part of the Advanced Microcontroller Bus Architecture (AMBA) family and is widely used for high-performance communication between processors, memory controllers, and peripherals. One of…
ARM Processors in High-Performance Computing and Desktop Environments: Current Landscape The adoption of ARM processors in high-performance computing (HPC) and general desktop use has been a topic of significant interest and debate. ARM architectures, known for their energy efficiency and scalability, have made substantial inroads into domains traditionally dominated by x86 processors. However, the transition…
NEON Operations and FPU Interrupt Behavior in ARM Cortex Processors The ARM architecture, particularly in its Cortex series processors, integrates advanced SIMD (Single Instruction, Multiple Data) capabilities through the NEON engine, alongside traditional Floating-Point Unit (FPU) operations. A critical aspect of these operations is their interaction with the processor’s interrupt mechanism. Understanding whether NEON operations…
ARM Cortex-M7 Unaligned Access Fault During memcpy Operation The issue at hand involves an unaligned usage fault occurring on an ARM Cortex-M7 processor during a memcpy operation. The memcpy function is used to copy data from the Backup SRAM (BKPSRAM) region to the SRAM1 region. This operation works flawlessly on a Cortex-M4 but triggers an…
SysTick Interrupt Configuration and NVIC Priority Settings The core issue revolves around the SysTick interrupt not triggering on an ARM Cortex-M0 processor integrated into the PGA970 system. The SysTick timer is a fundamental peripheral in ARM Cortex-M processors, often used for generating periodic interrupts for task scheduling or timekeeping. However, in this case, despite proper…
ARM Cortex-M4 PC Sampling and ITM Timestamp Synchronization Challenges The ARM Cortex-M4 microcontroller unit (MCU) provides powerful debugging and tracing capabilities through its Data Watchpoint and Trace (DWT) and Instrumentation Trace Macrocell (ITM) modules. These modules enable developers to generate Program Counter (PC) sample packets and local timestamps, which are critical for performance analysis and…
ARM Cortex-M7 UsageFault Triggered by Division-by-Zero with DIV_0_TRP Enabled The ARM Cortex-M7 processor, like other Cortex-M series processors, includes a UsageFault exception mechanism to handle various types of programming errors. One such error is a division-by-zero operation, which can be trapped by setting the DIV_0_TRP bit in the Configuration Control Register (CCR, address 0xE000ED14). When…
ARM Cortex-M4 AIRCR Register: BFHFNMINS and PRIS Bit Interaction The Application Interrupt and Reset Control Register (AIRCR) in the ARM Cortex-M4 processor is a critical register for managing system resets, interrupt priority grouping, and certain system control functionalities. Among its bits, BFHFNMINS (BusFault, HardFault, and NMI Non-Maskable Interrupt Secure) and PRIS (Prioritize Secure Exceptions) play…
ARM Cortex-M Microcontrollers for Medical Device Compliance and FDA Validation When developing medical devices, selecting the right microcontroller unit (MCU) is critical not only for functionality but also for ensuring compliance with regulatory standards such as those set by the U.S. Food and Drug Administration (FDA). ARM Cortex-M series microcontrollers are widely recognized for their…
ARM Cortex-M HPPIR Register and CPU Running Priority Interaction The Highest Priority Pending Interrupt Register (HPPIR) in ARM Cortex-M processors plays a critical role in interrupt handling by identifying the highest priority pending interrupt that is eligible for execution. However, its behavior can be influenced by the current running priority of the CPU, leading to…