agila-learning-examples/en/expanded-23-2/lesson-2/lesson.html

<!doctype html><html lang="en"><meta charset="utf-8"><title>Interrupts and driver boundaries</title><h1>Interrupts and driver boundaries</h1><p>15-minute session: read for 3 minutes, trace for 3, experiment for 7, and complete the check for 2. Spend longer whenever you need.</p><p>A hardware interrupt transfers control through architecture-specific entry code. A host callback is not a hardware interrupt. A driver validates device state, manages buffers, and observes ordering rules. Begin with a fake device so you can test invalid lengths and timeouts without writing to arbitrary hardware addresses.</p><p><strong>Practice and evidence:</strong> Design a read(buffer,length) contract with success, invalid argument, and timeout outcomes. Write one test per outcome before choosing an emulator and documented device.</p><h3>Practice and evidence</h3><p>Keep three notes: your prediction, the actual result, and why they match or differ. The completion check grades understanding; the practice task builds skill.</p><p><a href="https://git.agilaos.com/matt/open_kernel">Language reference: git.agilaos.com</a></p><p><a href="https://git.agilaos.com/matt/agila_open_tool">Language reference: git.agilaos.com</a></p></html>