"Reset Architecture in Embedded Systems: Designing Deterministic Startup, Recovery, and Fault Evidence" A microcontroller reset is often described as a simple event: the processor stops, returns to its reset vector, and starts the firmware again. That description is useful at the instruction-flow level, but it is electrically incomplete and architecturally dangerous. A real embedded product can reset because power has just appeared, the supply voltage collapsed, a watchdog detected stalled firmware, software deliberately requested a restart, an external supervisor asserted the reset pin, a debugger initiated a reset, or a device-specific protection mechanism detected an abnormal condition. Those reset events do not necessarily leave the system in the same state. RAM may or may not contain useful retained data. Peripheral registers may or may not have returned to reset values. External devices may still be running. A communication peer may believe a transaction is still active. Flash may have been interrupted during erase or programming. Motors, relays, power converters, radios, and actuators may have continued behaving while the processor restarted. Reset must therefore be treated as part of the system architecture, not merely as the first instruction executed by firmware. The central engineering principle is: A reset is a system state transition with a cause, a scope, retained state, and a required recovery policy. Reliable firmware must determine what happened, establish a known hardware state, preserve useful fault evidence, and only then resume normal operation. Click the following link to download the complete article in PDF format: https://lnkd.in/p/eCsp6gB7