DutyCycThermProtn_MDD

Module Design Document

For

DutyCycThermProtn

Dec 14, 2016

Prepared By:

Shruthi Raghavan

Software Engineering

Nexteer Automotive,

Saginaw, MI, USA

Change History

Table of Contents

1 DutyCycThermProtn & High-Level Description 5

2 Design details of software module 6

2.1 Graphical representation of DutyCycThermProtn 6

2.2 Data Flow Diagram 7

2.2.1 Component level DFD 7

2.2.2 Function level DFD 7

3 Constant Data Dictionary 8

3.1 Program (fixed) Constants 8

3.1.1 Embedded Constants 8

4 Software Component Implementation 9

4.1 Sub-Module Functions 9

4.1.1 Init: DutyCycThermProtn_Init1 9

4.1.1.1 Design Rationale 9

4.1.1.2 Module Outputs 9

4.1.2 Per: DutyCycThermProtn_Per1 9

4.1.2.1 Design Rationale 9

4.1.2.2 Store Module Inputs to Local copies 9

4.1.2.3 (Processing of function)……… 9

4.1.2.4 Store Local copy of outputs into Module Outputs 9

4.2 Server Runables 9

4.3 Interrupt Functions 9

4.4 Module Internal (Local) Functions 9

4.4.1 Local Function #1 9

4.4.1.1 Design Rationale 9

4.4.1.2 Processing 10

4.4.2 Local Function #2 10

4.4.2.1 Design Rationale 10

4.4.2.2 Processing 10

4.4.3 Local Function #3 10

4.4.3.1 Design Rationale 10

4.4.3.2 Processing 10

4.4.4 Local Function #4 10

4.4.4.1 Design Rationale 11

4.4.4.2 Processing 11

4.4.5 Local Function #5 11

4.4.5.1 Design Rationale 11

4.4.5.2 Processing 11

4.4.6 Local Function #6 11

4.4.6.1 Design Rationale 11

4.4.7 Local Function #7 11

4.4.7.1 Design Rationale 12

4.4.8 Local Function #8 12

4.4.8.1 Design Rationale 12

4.4.8.2 Processing 12

4.5 GLOBAL Function/Macro Definitions 12

5 Known Limitations with Design 13

6 UNIT TEST CONSIDERATION 14

Appendix A Abbreviations and Acronyms 15

Appendix B Glossary 16

Appendix C References 17

DutyCycThermProtn & High-Level Description

The purpose of the Thermal Duty Cycle Protection is to limit and protect the system from excessive use, based on motor rotational velocity and system temperature. It also provides protection status information for use by other functions.

Design details of software module

Graphical representation of DutyCycThermProtn

Data Flow Diagram

See FDD

Component level DFD

See FDD

Function level DFD

See FDD

Constant Data Dictionary

Program (fixed) Constants

Embedded Constants

Local Constants

Refer .m file

Software Component Implementation

Sub-Module Functions

Init: DutyCycThermProtn_Init1

Design Rationale

Refer FDD

Module Outputs

Refer FDD

Per: DutyCycThermProtn_Per1

Design Rationale

DutyCycThermProtn_Per1 function is divided into various functions to reduce the cyclomatic complexity.

The subsystems ‘Multiplier’ and ‘FilterPercMax’ are clubbed into ‘MultiFilterPercMax’ local function.

Store Module Inputs to Local copies

Refer FDD

(Processing of function)………

Refer FDD

Store Local copy of outputs into Module Outputs

Refer FDD

Server Runables

None

Interrupt Functions

None

Module Internal (Local) Functions

Local Function #1

Design Rationale

Name of local function matches with subsystem name from FDD

Processing

Local Function #2

Design Rationale

Name of local function matches with subsystem name from FDD

Note: The outputs of the function are Mult12Temp_DegCgrd_T_s15p0, Mult36Temp_DegCgrd_T_s15p0 and SlcTemp_DegCgrd_T_f32.

Processing

None

Local Function #3

Design Rationale

Name of local function matches with subsystem name from FDD

Processing

None

Local Function #4

Design Rationale

The subsystems ‘Multiplier’ and ‘FilterPercMax’ are clubbed into ‘MultiFilterPercMax’ local function.

Note: The outputs of the function are MaxOut_Uls_T_u16p0 and ThermLimSlowFilMax_Uls_T_f32.

Processing

None

Local Function #5

Design Rationale

Name of local function matches with subsystem name from FDD

Processing

None

Local Function #6

Design Rationale

Name of local function matches with subsystem name from FDD. Initializing ThermRednFac_Uls_T_f32 to 0.0 helps to avoid writing another statement in the if-conditional (optimized compared to FDD)

Local Function #7

Design Rationale

Name of local function matches with subsystem name from FDD

The if-action subsystem blocks for calculation of LoadDptLim and TempDptLim are clubbed together and optimized since the condition for the subsystem execution was same.

Local Function #8

Design Rationale

None.

Processing

None

GLOBAL Function/Macro Definitions

None

Known Limitations with Design

None

UNIT TEST CONSIDERATION

• Function UseInpLowr to be tested only as called by the component; input and output ranges will not be reached.

• Function UseInpLowr’s TableX must have strictly increasing elements.

Abbreviations and Acronyms

Glossary

Note: Terms and definitions from the source “Nexteer Automotive” take precedence over all other definitions of the same term. Terms and definitions from the source “Nexteer Automotive” are formulated from multiple sources, including the following:

• ISO 9000

• ISO/IEC 12207

• ISO/IEC 15504

• Automotive SPICE® Process Reference Model (PRM)

• Automotive SPICE® Process Assessment Model (PAM)

• ISO/IEC 15288

• ISO 26262

• IEEE Standards

• SWEBOK

• PMBOK

• Existing Nexteer Automotive documentation

References