Microcontroller-Based Temperature Monitoring and Control is an essential and practical guide for all engineers involved in the use of microcontrollers in measurement and control systems. The book provides design principles and application case studies backed up with sufficient control theory and electronics to develop your own systems. It will also prove invaluable for students and experimenters seeking real-world project work involving the use of a microcontroller. A basic mathematical and engineering background is assumed, but the use of microcontrollers is introduced from first principles. Techniques for the application of microcontroller-based control systems are backed up with the basic theory and mathematics used in these designs, and various digital control techniques are discussed with reference to digital sample theory. Author Dogan Ibrahim has used his engineering experience to write a book based on real-world applications. The first part of the book covers temperature sensors and their use in measurement, and includes the latest non-invasive and digital sensor types. The second part covers sampling procedures, control systems and the application of digital control algorithms using a microcontroller. The final chapter describes a complete microcontroller-based temperature control system, including a full software listing for the programming of the controller. Table of Contents Preface Microcomputer Systems Introduction Microcontroller systems Microcontroller features Microcontroller architectures The PIC microcontroller family Minimum PIC configuration PIC16F84 microcontroller - Pin configuration
- OPTION_REG register
- INTCON register
- TRISA and PORTA registers
- TRISB and PORTB registers
- Timer module and TMR0 register
PIC16F877 microcontroller Using C language to program PIC microcontrollers - FED C compiler variables
- Comments in programs
- Arrays
- Constants
- Enumerated constants
- Operators
- Program control in FED C
- Header files
- PIC PORT commands
- Built-in functions
- Using a LCD display
- Structures
- Unions
- User functions
- Pointers
- The pre-processor
PIC C project development tools Structure of a microcontroller based C program Program Description Language - START-END
- Sequencing
- IF-THEN-ELSE-ENDIF
- DO-ENDDO
- REPEAT-UNTIL
- SELECT
Example LCD project Exercises Further reading Temperature and its Measurement Temperature scales Types of temperature sensors Measurement errors - Calibration errors
- Sensor self heating
- Electrical noise
- Mechanical stress
- Thermal coupling
- Sensor time constant
- Sensor leads
Selecting a temperature sensor Thermocouple Temperature Sensors Thermocouple types Thermocouple junction mounting Thermocouple insulation - Standard insulating materials
- Mineral insulated thermocouples
Extension cables Thermocouple response times Thermocouple styles Thermocouple temperature voltage relationships - Using thermocouple reference tables
- Using power series method
- Using linear approximation
The theory of the cold junction compensation Microcontroller based practical thermocouple circuits PROJECT--Measuring temperature using a thermocouple and a microcontroller - The specifications
- The hardware design
- The software design
Exercises RTD Temperature Sensors RTD principles RTD types RTD temperature resistance relationship RTD standards - Class A standard
- Class B standard
Practical RTD circuits - Simple current source circuit
- Simple voltage source circuit
- Four-wire RTD measurement
- Simple RTD bridge circuit
- Three-wire RTD bridge circuit
Microcontroller based RTD temperature measurement PROJECT--Designing a microcontroller based temperature measurement system using an RTD - Specifications
- Design
- The circuit diagram
- Operation of the circuit
- Program listing
Exercises Thermistor Temperature Sensors Thermistor principles Thermistor types Self-heating Thermal time constant Thermistor temperature-resistance relationship - Temperature-resistance table
- Steinhart-Hart equation
- Using temperature-resistance characteristic formula
- Thermistor linearization
Practical thermistor circuits - Constant current circuit
- Constant voltage circuit
- Bridge circuit
- Non-inverting operational amplifier circuit
- Inverting operational amplifier circuit
Microcontroller based temperature measurement PROJECT--Designing a microcontroller based temperature measurement system using a thermistor - Specifications
- Design
- The circuit diagram
- Operation of the circuit
- Program listing
Exercises Integrated Circuit Temperature Sensors Voltage output temperature sensors - Application of voltage output temperature sensors
Current output temperature sensors - Applications of current output temperature sensors
Digital output temperature sensors - Applications of digital output temperature sensors
PROJECT--Using a digital output sensor to measure the temperature - The hardware
- The software
Exercises Digital Control Systems and the z-transform The sampling process The z-transform - Properties of the z-transform
- z-transform from the Laplace transform
Inverse z-transform - Power series method
- Partial fraction expansion method
The pulse transfer function - Open-loop digital control systems
- Open-loop time response
- Closed-loop control systems
- Closed-loop time response
Exercises Stability Jury's stability test for small systems The root-locus technique Digital control algorithms Temperature control using digital computers - Bang-bang control of temperature
- Control of temperature using continuously variable controller
- Ziegler-Nichols PID tuning algorithm
Digital realizations - Direct programming
- Serial programming
- Parallel programming
- Canonical programming
Realization of the discrete PID controller Problems with the standard PID controller Choosing a sampling interval Exercises Case Study: Temperature Control Project Overview The mathematical model - Mathematical model of the tank
- Mathematical model of the heater
- Mathematical model of the temperature sensor
The circuit diagram Identification of the system Pulse width output of the microcontroller Design of a PI controller - The software of the PI controller
- Results
Design of a PID controller - The software of the PID controller
- Results
Compensating for heat losses Other considerations Exercises Appendix A: Platinum RTD Sensor Resistances (α = 0.00385) Appendix B: ASCII Code Appendix C: FED C Compiler Library Functions Glossary Index Paperback; 256 pages
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