Introduction to I&C software

Major Activities

• Requirements Definition
  • What do we want to achieve?
  • define requirements (specifications)
• Design
  • How to achieve?
  • define DSA
  • breakdown into components and their architecture
• Implementation
  • convert design to code
• Verification
  • Is our implementation correct?
  • wrt requirements & design

Arranging activities

eg. Waterfall model

flowchart TB

A[Requirements
Definition] --> B[Design] --> C[Implementation] --> D[Verification]

Freeze an activity before going to next step. Can be used for critical systems, since requirements unlikely to change while developing.

Instrumentation and control systems

flowchart LR

A[Physical
Process] --"temperature
neutron flux"--> B[Sensors] --"voltage/
current"--> C[Controller
PLC] --"voltage/
current"--> D[Actuators] --> A

Program pseudocode

every 10 ms :
    input_signal <-- read from board
    regulating_signal := compute(input_signal)
    regulating_signal --> output to board

Features

• reactive
  • never terminate
• real time performance requirements
• important to safety
  • failure not acceptable