ARM Cortex-A8 IRQ Enable and Hard Fault Trigger The issue at hand involves enabling IRQ (Interrupt Request) on an ARM Cortex-A8 processor, specifically within the AM3354 SoC, which results in an immediate hard fault. The user attempted to enable IRQ by writing assembly code to modify the CPSR (Current Program Status Register) to clear the…
ARM Cortex-M Memory Storage Issue During Data Manipulation The core issue revolves around the inability to store the result of an addition operation back to a specific memory location in an ARM Cortex-M-based system. The code provided attempts to load three values from memory, add them together, and store the result back into memory. However,…
ARM Cortex-A Level 0 Translation Fault During Stack Pointer Adjustment The issue at hand involves a Level 0 Translation Fault occurring during the execution of an STP (Store Pair) instruction in an ARM Cortex-A processor operating at Exception Level 2 (EL2). The fault manifests when the stack pointer (SP) is adjusted by subtracting 48 bytes…
SIM800 GSM Clock Function Interferes with SMS-Based Control Logic The core issue revolves around the integration of a GSM clock function (send_clock) into an SMS-controlled irrigation system using the STM32F103 microcontroller and SIM800 GSM module. The system operates in three modes: manual, semi-automatic, and automatic. The first two modes function correctly, but the automatic mode,…
ARM Cortex-A9 Banked Register Restoration Challenges During Context Switching When working with the ARM Cortex-A9 processor, particularly in the context of real-time operating systems (RTOS) and exception handling, developers often encounter challenges related to the restoration of banked registers during context switching. The Cortex-A9, like other ARM processors, employs a banked register scheme to optimize…
ARM Cortex-M USB Host Performance Issues and Concurrent Device Handling When designing an embedded system that integrates multiple USB devices such as keyboards, flash drives, printers, and potentially barcode scanners, the choice of the microcontroller unit (MCU) is critical. The ARM Cortex-M series offers a range of processors that can handle these tasks, but selecting…
ARM Cortex-A53 Stage 2 Translation Setup and EL2 Hangs When enabling stage 2 translation on an ARM Cortex-A53 processor, such as the one found in the Raspberry Pi 3B+, the system may hang during the configuration process in Exception Level 2 (EL2). This issue typically arises when setting up the Virtualization Translation Table Base Register…
Cortex-M33 FPU Underflow and Input Denormal Exception Flag Conditions The Cortex-M33 Floating Point Unit (FPU) is a critical component for handling floating-point arithmetic in embedded systems. It provides hardware support for single-precision floating-point operations, which are essential for applications requiring high precision and performance. However, the FPU can generate specific exception flags under certain conditions,…
ARMv8 Exception Level and Execution State Transition Challenges The ARMv8 architecture introduces a sophisticated exception level (EL) model and execution state (AArch32 and AArch64) framework, which provides flexibility but also complexity when transitioning between different privilege levels and execution states. A common scenario in baremetal systems involves starting execution in AArch64 at EL3 during reset…
ETM Trace Data Synchronization Errors in Keil IDE The Embedded Trace Macrocell (ETM) in ARM Cortex-M4 processors is a powerful tool for real-time debugging and trace analysis. However, signal integrity issues on the ETM trace bus can lead to synchronization errors, particularly when interfacing with debug tools like Keil IDE. These errors manifest as "Trace…