Misc

Introduction: The Illusion of Sequential Execution

When you write code, you naturally think in terms of sequential execution: instruction A happens, then instruction B, then instruction C. This mental model works perfectly—until you start writing concurrent code or working with hardware. Then you discover that modern CPUs, compilers, and memory systems conspire to execute your code in ways you never imagined.

The truth is that sequential consistency is largely an illusion maintained by your compiler and CPU to make programming tractable. But when multiple cores or threads are involved, that illusion breaks down in spectacular and subtle ways.

The Hardware Testing Challenge

When developing hardware, the challenging phase begins after the prototype is designed and PCBs are manufactured. The easy part—conceptualization and board design—is behind you. What follows is infinitely harder:

• Making boards electrically alive and verifying proper operation with electrical jigs and test equipment
• Programming and validating firmware behavior
• Testing the complete system’s functionality under real-world conditions
• Building the infrastructure—both hardware and software—to support comprehensive testing

For devices communicating via NMEA protocols, this challenge is compounded by the complexity of marine electronics standards and the difficulty of simulating real maritime data streams.