Embedded C volatile registers: solving I/O ordering with minimal code
Use volatile for hardware register accesses, verify with assembly and a hardware debugger, and avoid over‑using it to keep performance high.
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embeddedcUsing volatile Correctly for Hardware Register Access in Embedded C
How and why to use volatile for memory-mapped hardware registers in embedded C, with a worked register-map example, assembly-level verification, and the limits of what volatile guarantees.
A Lock-Free SPSC Ring Buffer for ISR-to-Main-Loop Data in Embedded C
An architecture note on a lock-free single-producer/single-consumer ring buffer for moving data from an ISR to the main loop in embedded C: minimal design, trust boundaries, overflow policy, checks, and failure modes.
Why Your Polling Loop Hangs at -O2: The volatile Qualifier in Embedded C
Your UART polling loop works at -O0 but hangs at -O2. The culprit: missing volatile on memory-mapped registers. A worked example shows why volatile exists, how to apply it correctly, what it doesn't do, and how to verify the generated assembly.
Fixed-Point Arithmetic on FPU-Less Microcontrollers: A Practical Q-Format Guide
On microcontrollers without a hardware FPU, float math is emulated in software and costs dearly. This guide shows how Q-format fixed-point arithmetic works, with a complete Q15 sensor-filter example, overflow analysis, and on-target verification steps.
Lock‑Free Circular Buffers in Embedded C: A Practical Guide for ISR‑to‑Main‑Loop Data Exchange
Learn how to build a fast, interrupt‑safe, single‑producer/single‑consumer circular buffer in C. The post covers sizing, head/tail atomicity, power‑of‑two optimizations, pitfalls, and a UART ISR example.
Diagnosing Stale Peripheral Register Reads in Embedded C Due to Missing volatile
Identify why hardware status flags appear stale, locate missing volatile qualifiers, apply the fix, and verify the solution.
Precision Placement: Using GCC Section Attributes in Embedded C
Learn how to use GCC's __attribute__((section)) and linker scripts to precisely place code and data in specific memory regions to optimize RAM and Flash usage in embedded C.
Using volatile for Safe Memory‑Mapped I/O Access in Embedded C
Learn how to declare peripheral registers with the volatile qualifier, verify compiler output, and add memory barriers when needed to guarantee correct hardware interaction.