Alessandro Salvato

In C, the & symbol is far more than a simple operator. It represents multiple fundamental concepts of the language: obtaining memory addresses, performing bitwise operations, and expressing logical conditions through &&. This deep dive explores every meaning of the ampersand, from pointers and pass-by-reference patterns to bit masking and embedded firmware use cases. Understanding & means understanding how C really works under the hood.

Link Time Optimization (LTO) transforms embedded firmware from separate compilation into whole-program reasoning. With Keil and armclang, it removes dead code, devirtualizes C++, reduces veneers and shortens branch distances. The result is smaller flash, fewer pipeline flushes, lower ISR latency and improved WCET predictability — measurable directly inside the map file.

SEGGER RTT (Real-Time Transfer) enables high-speed, bidirectional communication between an embedded target and a host PC using only RAM and the debug interface. It removes the need for UART, dedicated pins, and interrupts, providing high-throughput logging with minimal real-time impact. Suitable for both white-box instrumentation and black-box-like telemetry workflows, RTT enhances observability in professional embedded systems development.