Secure and Non-Secure Domain Execution Time Discrepancy in ARM Cortex-M23 The ARM Cortex-M23 processor, which is part of the ARMv8-M architecture, introduces the concept of TrustZone for microcontrollers, enabling the division of code execution into secure and non-secure domains. This separation is crucial for applications requiring robust security, such as IoT devices, where sensitive operations…
Understanding AXI-to-DRAM Address Mapping in ARM Cortex-A53 Systems The ARM Cortex-A53 processor, commonly used in systems like the Zynq UltraScale+ MPSoC, relies on the Advanced eXtensible Interface (AXI) for memory transactions. AXI is a byte-addressable protocol, meaning it uses byte-level granularity for addressing memory. However, DRAM (Dynamic Random Access Memory) operates on a different addressing…
ARM Cortex-M3 For Loop Cycle Count Calculation The cycle count of a for loop in an ARM Cortex-M3 microcontroller, such as the LPC1768, is a critical consideration for developers working on real-time systems, timing-sensitive applications, or performance optimization. The cycle count depends on several factors, including the compiler’s optimization level, the specific instructions generated, and…
ARM GICv4 Virtual Interrupt Injection Capabilities The ARM Generic Interrupt Controller (GIC) architecture has evolved significantly over its versions, with GICv4 introducing support for virtual interrupt injection, specifically Virtual Locality-specific Peripheral Interrupts (vLPI). This capability is crucial for virtualization scenarios, where hypervisors manage multiple virtual machines (VMs) and need to efficiently handle interrupts for virtualized…
ARM Cortex-A9 FPU-Enabled Memcpy Performance Discrepancy The ARM Cortex-A9 processor, known for its dual-core architecture and advanced features like the Floating Point Unit (FPU) and NEON extensions, is widely used in embedded systems for its balance of performance and power efficiency. However, a common issue arises when developers enable the FPU for memory copy operations,…
ARM Cortex-M0 Task Switching Failure Due to Incorrect Handler Mode Execution Issue Overview The core issue revolves around the failure of task switching in an ARM Cortex-M0-based system running the µC/OS-II real-time operating system (RTOS). The system enters an infinite loop at OSStartHang when attempting to switch tasks, but the application runs correctly without the…
ARM Cortex-M33 Instruction Fetch and Memory Access Relationship The ARM Cortex-M33 processor, as implemented in the Arm Musca Board A1 with Corelink SSE 200 IP, features a dual-core architecture with a three-stage pipeline. One of the key aspects of debugging and tracing on this platform involves understanding the relationship between instruction execution and memory access….
UART FIFO and DMA Mode Configuration in LPC17xx and Similar ARM Microcontrollers The integration of UART (Universal Asynchronous Receiver/Transmitter) with DMA (Direct Memory Access) in ARM-based microcontrollers, such as the NXP LPC17xx series, is a powerful feature that can significantly enhance data transfer efficiency. However, the interaction between UART FIFOs (First-In-First-Out buffers) and DMA modes…
ARM Cortex-M4 Cross Trigger Matrix Configuration and Bus Fault Analysis The ARM Cortex-M4 core, when integrated into a System-on-Chip (SoC) such as the Cypress TII MCU, provides a Cross Trigger Interface (CTI) and Cross Trigger Matrix (CTM) to enable sophisticated debugging and event management capabilities. These features allow developers to route debug events, such as…
ARM Cortex-A55 Cache Verification Challenges in EL1 The ARM Cortex-A55 processor, like many modern ARM cores, features a hierarchical cache architecture with separate L1 instruction and data caches, as well as a unified L2 cache. While the ARM architecture provides mechanisms to access and manage caches at higher exception levels (EL3), performing direct cache testing…