Requirements Analysis and Design for Heating Control System V10

This assignment provides a comprehensive requirements analysis specification for the Central Heating Control System V10, a real-time system. The analysis is presented through Data Flow Diagrams (DFDs), Entity Relationship Diagrams (ERDs), RT-SASD modifications, Control Flow Diagram extensions (CFDs), Process Specifications (PSPECs), a Data/Requirements Dictionary, and Control Specifications (CSPECs). The document includes detailed diagrams illustrating system processes, such as heating ducts, gas meter supply, heating unit operations, fan control, system clock, and temperature detection. It also features control specifications using a process activation table and state machine diagrams for critical processes. The assignment further details system control panel functionalities, including temperature configuration, heating program settings, and manual overrides, all supported by a comprehensive data dictionary defining system components and events. In conclusion, the assignment provides a thorough analysis of the real-time system requirements for the Central Heating Control System V10.

Heating Control System V10
(CHCSV10)
Assignment 1
Real Time Analysis

Introduction
This paper presents a requirements analysis specification of a Real-Time System; Central
Heating Control System V10. The result of the analysis is presented in form of a;
 Data Flow Diagrams (DFDs)
 Entity Relationship Diagrams (ERDs)
 RT-SASD modifications and components
 Control Flow Diagram extensions (CFDs),
 Process Specifications (PSPECs)
 Data/Requirements Dictionary
 Control Specifications (CSPECs)
Entity Relationship Diagram

Control/Data Flow Diagram (Level 0)

Control/Data Flow Diagram (Level 1)

Process 1 Control/Data Flow Diagram (Level 2): Heating
Ducts
Process 2 Control/Data Flow Diagram (Level 2): Gas Meter
Supply

Process 3 Control/Data Flow Diagram (Level 2): Heating
Unit

Process 4 Control/Data Flow Diagram (Level 2): Heating
Unit Fan
Process 5 Control/Data Flow Diagram (Level 2): System
Clock

Process 6 Control/Data Flow Diagram (Level 2):
Temperature Detector
Process 7 Control/Data Flow Diagram (Level 2): Display

Control Specification (Process Activation Table)
 Only for starting the heating when temperature falls below the set value AND
stopping the heating when the temperature goes beyond the specified value during
the heating process.
Current temp below
specified level?
Activate Activate Activate Activate Activate
TRUE 1.2 2.2 3.3 4.2 7.1
FALSE - - - - -
New temperature is
above specified level
Activate Activate Activate Activate Activate
TRUE 1.3 2.3 - 4.3 7.1
FALSE 7.1 - - - -
Duck was manually
closed?
Activate Activate Activate
TRUE 7.1 - -
FALSE 1.2 7.1 -
Duck available Activate Activate Activate
TRUE 1.2 7.1 -
FALSE 7.1 - -
Gas meter available? Activate Activate Activate
TRUE 2.2 7.1 -
FALSE 7.1 - -

State Machine Diagrams
Heating Unit Process

Gas Meter Supply Process
Heating Unit Fan

Process Specification
 Verify If current temperature is below the specified value
get specified_temp_level;
Read current_temp
if(current_temp < specified_temp_level)
activate_heating_unit = true
else
activate_heating_unit = false
Current temperature is compared with the specified temperature;
if the current temperature falls below the specified value; the heating process
is activated; which requires a number of processes.
Verify availability of heating components to activate heating
get heating_unit_fans_status
get heating_unit_status
get gas_meter_supply_status
get heating_ducts_status
get time
get day
if(heating_unit_fans_status = available
AND heating_unit_status = available
AND gas_meter_supply_status = available
AND heating_ducts_status != manually_closed){
open_ducts = true
start_gas_flow =true
start_fans =true