Embedded real-time software; model for project

Embedded software

Embedded software is the program stored in the non-volatile memory (ROM/flash) of a microcontroller or microprocessor that is built into a device (a washing machine, an instrument, a car ECU) to perform a dedicated function. It has a fixed purpose, limited memory and CPU power, and works directly with the hardware (sensors, actuators, ports).

Real-time software

Real-time software must produce correct results within a specified time deadline; correctness depends on both the logic and the time at which the result is produced. A hard real-time system (airbag, pacemaker) fails if a deadline is missed; a soft real-time system (video playback) only loses quality. It uses interrupts, timers and often an RTOS with priority scheduling.

Suitable model for an academic project

Assume a microcontroller-based project (for example a temperature-controlled system with an LCD and a keypad). The suitable model is iterative/incremental (or prototyping) development:

• The requirements of a student project are not fully fixed, and the hardware is built step by step.
• Build and test one module per iteration (sensor reading, display, control, communication), with a working version after each, and integrate gradually.
• An early prototype on a breadboard or simulator confirms feasibility, and feedback from the supervisor guides the next increment.
• Test each increment before adding the next; finish with system testing and documentation.