Embedded System Lab Manual[1]

Microprocessor based Embedded system

ECE3637 Lab Manual

Revised DateApril, 2015DEPARTMENT OF ELECTRICAL ENGINEERING

THE UNIVERSITY OF LAHORERevision History

Revised DateRevised ByRevised Topics

April 23,2015Dr. Ghulam AbbasEngr. Shahzad AhmedLab.01 Using KEILLab.02 Software Delay

Lab.03 8051 IO Ports

Lab.04 Switch De-bounceLab.05 Soft Timer

Lab.06 8051 Timers

Lab.07 PWM generation

Lab.08 Interfacing a DC motor

Lab.09 8051 External Interrupt

Lab.10 Serial Communication

Lab.11 8051 Timers and Serial Interrupts

Lab.12 Switch De-bounce using FSM

Lab.13 LCD interfacingLab.14 Keypad matrix

Lab.15 Interfacing ADC

Lab.16 Stepper Motor Interfacing

January 20, 2013DR. Musharraf Ahmed HanifEngr. Shahzad AhmedLab.01 Setup development for STM32Lab.02 Bare bone project for STM 32

Lab.03 Configure a GPIO pin as output

Lab.04 Create a software delay

Lab.05 Configure a GPIO pin as input using debugger

Lab.06 De-bounce a witch input and count its state changes

Lab.07 implement a time cyclic executive using Timer

Lab.08 Start development and debugging of course projectLab.09 Implementing FSM

Lab.10 implement a multistate machine

Lab.11 Implement a multistate cyclic executiveLab.12 Using LCD library

Lab.13 Using USART library

Lab.14 Keypad matrix

Lab.15 ADC

Lab.16 Demonstration and Evaluation of Course project.

January 20, 2012Hassan Bin AhmedLab.01 8051 assembler and simulatorLab.02 Examining the CY flag and the stack

Lab.03 Simulating I/O ports

Lab.04 Data transfer

Lab.05 Arithmetic operations-1

Lab.06 Arithmetic operations-11

Lab.07 ASCII and BCD conversion

Lab.08 Testing 8051 I/O ports

Lab.09 Timer programming

Lab.10 Event counter programming

Lab.11 8051 serial port interfacing

Lab.12 Interfacing an LCD to 8051

Lab.13 Interfacing key pad matrix

Lab.14 interfacing a sensor

Lab.15 Interfacing a stepper motor

Lab.16 8051 programming in C

CERTIFICATE OF APPROVAL

It is certified that the lab manual titled Microprocessor based embedded system, in scope and in quality, covers the objectives and topics defined in the course outline. Remarks by Mentor: ----------------------------------------------

Dr. Ghulam Abbas

Assistant Professor

Department of Electrical Engineering

The University of Lahore

Remarks by HOD:

-------------------------------------------------Dr. Asrar ul Haq Sheikh

Professor

Department of Electrical Engineering

The University of Lahore

TABLE OF CONTENTS

S. NoTOPICSPAGE NO.

1Using KEIL6

2Software Delay10

38051 IO Ports14

4Switch De-bounce19

5Soft Timer23

68051 Timers26

7PWM generation51

8Interfacing a DC motor to 8051 55

98051 External Interrupt59

10Serial Communication42

118051 Timers and Serial Interrupts45

12Implementing Switch De-bounce using FSM48

13LCD interfacing51

14Keypad matrix55

15Interfacing ADC59

16Stepper Motor Interfacing63

Lab. 01Experiment title:Using KEIL to write an 8051 Assembly language program and burning its hex file to the controller.

Introduction and Theory: Keil is basically an Integrated development environment (IDE) for developing embedded projects supporting a wide range of microcontrollers based on ARM, Cortex-M and Cortex-R. The IDE integrates the source editor, compiler, assembler, linker, debugger and a very strong simulator all in one tool. It is easy to use.

GeniusPro540/840 is used to burn, program and erase the ROM of a wide range of microcontrollers. Pre Lab Preparation:

Download and install KEILl Vision5 from www.keil.comEquipment:

Personal computer (Hardware).

AT89S52 (Hardware)

G540 / G840 programmer. (Hardware) KEIL Vision5/4 installed. (Software) GeniusPro540 / GeniusPro840Procedure: Run the KEIL software. Click on project from the menu and then select new uVision project. Name the project toggle and save it in a new folder with the name My First Project.

Copy a startup file.asm for the 8051 in My First Project if not copied automatically.

A window will open to select the target device. Select ATMEL and then AT89S52 and click on ok.

Select new from the menu to create a source file.

A text window will open to write the code.

Write the code given below in asssembly language to toggle ports 1 & 2 after a delay.

Save the source file with the extension .a51 or.asm.

Add this file to your project.

Go to target options and change the Xtal to 11.0592 MHz from 33MHz.

Go to Output tab and click on Hex file.

Build and rebuild the project for zero errors and warnings.

Select debugger. Start the debug session and run it.

Select peripherals. Select port 1 &2 for simulation results.

Plug the 8051 controller to the Genius programmer and make a successful connection.

A window showing the memory with addresses and its contents is displayed.

Load the hex file of your project.

Program the 8051 which is now ready to use.Observations and Results:

Once the program is assembled, go to the project folder count and enlist the number of new files with their extensions. Run the debugger & simulator to see the results.

Analyze the memory of 8051 before and after erasing the chip

Ports 1 & 2 will toggle with alternate bit pattern after a delay.Learning outcomes:

The students must be able to develop a project written in an assembly language.

Get to know how to use the source editor, compiler/debugger, simulator in an integrated development environment and creating the hex file. Learn to get the hex file burnt to the microcontroller using a universal programmer.

Questions:

What is an IDE? What is the name and version of the IDE used in this lab?

What is an assembler? What are its input and output files? Which assembler is used in this lab?

What is a linker? What are its input and output files? Which linker is used in this lab?

What is a simulator? Which simulator is used in this lab?

Open the folder My First Project and find out how many files are contained in it after completing all the steps?

Write down the names of the files in folder My First Project that contain software code in them for the target device.

What is the name and extension of uVision project file?

What is the purpose of startup (.s) file?

What is the purpose of linker script (.lst) file?

What is the purpose of G840 / G540?

Each student is required to perform the lab and submit the following Performa along with the lab report.1 = Unsatisfactory 2 = Fair 3= Satisfactory 4 = Very good 5= Excellent QuestionsRating

(1 to 5)Remarks

1. To what extent did you learn on the material in the lab?

2. Are you able to apply knowledge gained in the lab to similar problems?

3. Are you able to analyze and interpret data recorded in the lab?

4. Are you able to identify, formulate and solve electrical engineering problems based on the knowledge acquired in the lab.?

5. Can you design a system, component or process to fulfill certain specifications based on the knowledge acquired in the lab?

6. Were you able to function as a group in the lab?

7. Were you able to interpret effectively the procedures and questions asked in the lab?

8. Comment whether your work in the lab has an impact on the society.

Additional Comments (if any)Lab. 02Experiment title:Implementing a software delayIntroduction and Theory:

All I/O ports in 8051 by default when powered up are pulled up internally except for Port 0 which is pulled up externally. All I/O ports are by default inputs but once zero written to a port it is an output. To use it as an input reprogram it by writing 0 to it. A good practice is to write a 1 for an input and a zero for an output. Three of the ports are multiplexed. Port 3 is having serial com, external interrupts and timers. Two of the ports are used for addressing mode for accessing external memory. For C language programming a C Kiel compiler is required. (GCC Sourcery)Pre Lab Preparation:

Study the I/O ports programming in C from the book (8051 by M. Ali Mazidi). Study the pin configuration of the 8051 trainer.

Equipment: 8051 trainer available in the lab Universal programmer

DMM

Computer

KEIL uVision4

G540Procedure:

To test the operation of the ports of your 8051 Trainer in the lab you can download the C program for Toggling LEDs on P2 given below:

For you Compiler, make sure the hex option in the Link is checked so the hex file for the above program is produced. The source file will be saved with .c extension.

Now, follow the steps given in Lab 1 to download the hex file into the 8051 Trainer. The above test program toggles the P2 of the 8051. Use a logic probe or the LEDs of the 8051 Trainer to watch the bits of the ports toggle on and off. Change the time delay in between the "on" and "off" states but make sure the time delay is long enough that you can observe the LED going on and off.Observations and Results: To create a loop of 10,000 iterations we need data type of (unsigned char, unsigned int). To create a loop of 200 iterations we need data type of (unsigned char, unsigned int). In the toggle program reduce the size of the delay to point in which the LEDs looks to be on all the time (no longer toggling). How many millisecond is that?Learning outcomes:

To toggle and test the 8051 Trainer and its ports using C programQuestions:

What is the opposite of 0x55?

What is the opposite of 0xAA? List all ports of 8051

In this Lab, which ports were tested?

Give the pins of P3 used for TxD and RxD.

Which ports of the 8051 have internal pull-up resistors?

Which ports of the 8051 require the connection of external pull-up resistors in order to be used for I/O?


(1 to 5)Remarks









Additional Comments (if any):

Lab. 03Experiment title:Programming the I/O ports

a) Port mirror

b) Implementing sliding LEDs

Introduction and Theory:

All ports of 8051 are pulled up internally except the port 0 which is pulled up externally. All ports are input by default when powered up. When first 0 is written to a port it becomes an output. In order to use it as an input it must be reprogrammed by writing 1 to it. All these ports are bit accessible and byte accessible.

Pre Lab Preparation:

Students must perform lab 2 before performing this lab.

Equipment:KEIL simulator

8051 trainer/AT 89s52Pin configuration of AT 89s52 is given below: Procedure:

In this Lab we test the 8051's port for input operation. Download the C program for Sending P1 Switch Data to P2 LED given below.

Then, compile, download and run the program. This program gets data from P1 and sends it to P2.Implementing sliding LEDs Implement the following code to implement sliding led on P1.

Observations and Results: Any change of status of the switches connected to P1 will be instantly reflected on LEDs connected to P2. Write and run a program to get data from P1 and after adding a fixed value of 5 send it to P2. Set the switches and examine the LEDs and verify the result. Use sbit keyword to access bit 5 of port 1 and make it an input and bit 2 of port 2 connected to an led.Learning outcomes:Configuring ports as inputs and outputsQuestions:

On the 8051 Trainer, which port is connected to the DIP switches? On the Trainer, which port is connected to the LED 7segment?

In this Lab, which port of the 8051 Trainer did we use for outputting?

In the 8051, explain why we must write "1" to a port in order for it to be used for input.

The Maximum value we can input from P! DIP switches is (in binary), .hex, and .decimal.

Upon reset, all the ports of the 8051 are configured as ______ (input, output).

To make all the bits of P1 an input port we must write ____ hex to register______.

Write a simple short program to get a byte of data from P1 and after incrementing it once sends it to P2.

Assignment:

Write a code such that P1.0 is an input connected to a switch and P1.7 is an output connected to a led and P2.0 is connected to the oscilloscope

a) If switch = 0 then a square wave of 1Hz IS generated at P2.7 and the led blinks with the same frequency.

b) If switch = 1 then a square wave of 2Hz IS generated at P2.7 and the led blinks with the same frequency.

Write a code to continuously monitor the input pin connected to TTL mode square wave generator and send it to the output pin connected to an LED. Each student is required to perform the lab and submit the following Performa along with the lab report.1 = Unsatisfactory 2 = Fair 3= Satisfactory 4 = Very good 5= Excellent QuestionsRating

(1 to 5)Remarks










Lab. 04Experiment title:Implementing an input counter using switch de-bounceIntroduction and Theory:

In many systems we need input counters to keep track of an action. Switch debounce tales place between 100ms to 500ms on both at press as well on release. Due to the phenomena of switch debounce has to be handled in software such that a single push results in a single input.Pre Lab Preparation:

Lab-3 and lab-4 must be performed before implementing this lab. A delay can be generated by writing a software code. For example by implementing loops. A grip on the structures of loops in C is important. Equipment:KEIL uVision4/5 compiler

8051 trainer/AT 89s52Universal programmer G540/G840Procedure:

Write and test a C program to count up in binary on your 8051 Trainer. The counter should start counting from 0 and go up to 255 after a delay of 1 second. Change the time delay in between the counts. Make sure the time delay is long enough that you can observe the LED counting up. In the above step,the maximum count was FFH(or 255). Modify the above program to set maximum count to 10 (00001010).

Change the maximum count to the value of your age and observe the LED counting up to that number. The value of the counter is sent to port 1. Now modify the above code such that P2.0 is the input connected to the push button. Each time when the push button connected to P2.0 is pressed the counter increments and is sent to P1. Also test your program to verify the counter variable overflow. You will have to write Use the code for switch de bouncing to implement a push button.

Test your program on the Keil simulator as well as 8051 trainer.Observations and Results:

Verify the above scenario using KEIL simulator.Learning outcomes:

Be able to write a software delay to implement a counter. Developing a portable system..

Questions:

If variable is 8 bit in length used in a counter, what would be the value in the counter after 256 iterations if it started from 0.


(1 to 5)Remarks










Lab. 05Experiment title:Implementing a soft timer on 8051 trainer using C Introduction and Theory:

In many systems such as microwave oven we use timers to keep track of an action.Pre Lab Preparation:

Lab-3 and lab-4 must be performed before implementing this lab. A delay can be generated by writing a software code. For example by implementing loops. A grip on the structures of loops in C is important. Equipment: Keil uVision4/5 compiler

8051 trainer

Universal programmer

Procedure:

Write a C program to implement a timer which can down count using 8051 trainer.

It should show the binary count on the LEDs connected to one of the ports for example P2.

A push button is connected to P1.0.

P0 will be configured as an input.

The dip switched connected to this P0 will be used to load the timer maximum value.

Switch de-bounce will be implemented for P1.0.

Write a C program using KEIL such that the timer maximum value is loaded via the dip switches connected to P0.

When the push button connected to P1.0 is pressed and released the timer starts down counting from the maximum value loaded by the dip switches to zero.

This down counting binary pattern must be shown on led connected to P2.

Write a delay function such that there is a delay of exactly one second between the counts.

When the down count reaches zero an LED connected to P1.1 is turned on.

One more feature is that whenever the push button connected to P1.0 is pressed and released during the down counting the timer stops and when it is again pushed the timer resumes. (optional)

Observations and Results:

Verify the above scenario using KEIL simulator.Learning outcomes:

Be able to write a software delay to implement a timer. Developing a portable system..

Questions:

How can we implement an infinite loop using for loop?

How can we time out an infinite loop?


(1 to 5)Remarks










Lab. 06Experiment title:Timer programminga) Generating a Hardware delay using an 8051 timerb) Implementing a pulse counter using an 8051 timer


Basic Timer registers:

Timer 0 register (16 bit)

Timer 1 register (16 bit)

TMOD register (8 bits, used to select different timer modes)


Study of 8051 timer and its registers from the book

Equipment: 8051 Trainer

8051 KEIL Compiler

Oscilloscope Speaker (optional) 74LS04 Inverter (optional) Universal programmerProcedure:Hardware delay: One can use the 8051 Timer to generate time delay to toggle a bit using the following program: Compile and run it on the 8051 trainer to make sure it works.

Write a program using a 8051 Timer to generate a 500 Hz square wave frequency on pin P2.7 Then examine the frequency using the oscilloscope. Modify the count value to make sure that the frequency is exactly 500 Hz.

Write a program using a Timer to generate a 1 kHz square wave frequency on pin of P2.0 Then examine the frequency using the oscilloscope. Modify the count value to make sure that the frequency is exactly 1 kHz.Pulse counter:

Connect the square wave from function generator to pin P3.4 for Timer 0 and set the frequency to 1 Hz. Write and run a program for counter/timer 0 to count up from 00 to a maximum of 255 (FFH) as each pulse is fed into the 8051. The count is displayed in binary on the 8 LEDS of 8051 Trainer. Notice that the binary numbers displayed for the count goes from 00 to FF (00000000- 11111111 in binary or 00 -255 in decimal).Observations and Results: Examine the frequency in all steps using oscilloscope. Modify the count value to achieve the exact value.

Simulate the above steps to see the 8051 timer register values on run time using Keil simulator.

Use KEIL simulator to simulate all the above steps to analyze the status of the timer registers working in counter mode.

Learning outcomes:

To program the 8051 timer in different modes.

Learn to use 8051 timers as pulse counters.

Questions:

What is the function of the TMOD register

Is TMOD a bit addressable register?

What is the difference in the timer lengths in modes 0,1 and 2?

In which register do we find the timer start bits and timer rollover bits.

Explain the role of the C/T bit in the TMOD register. How is the 8051 used as an event counter to count an external event? If timer/counter 0 is used as an event counter, what is the maximum count for the following modes?a)Mode 1b) Mode 2

Indicate which pin is used for the following. (a) timer/counter 0 (b) timer/counter 1 If timer/counter 0 is used in mode 1 to count an external event, explain when TF0 is set to high. If timer/counter 1 is used in mode 2 to count an external event, explain when TF0 is set to high.Each student is required to perform the lab and submit the following Performa along with the lab report.1 = Unsatisfactory 2 = Fair 3= Satisfactory 4 = Very good 5= Excellent QuestionsRating

(1 to 5)Remarks










Lab. 07Experiment title:PWM generation

a) Using software delayb) Using 8051 timers


Square wave of a specified frequency is used as a clock in computer systems. PWM signal is used in modulation. PWM signal of required duty cycle can be generated using I/O ports of 8051 microcontroller. PWM signals are used in communication systems. It is also used in photovoltaic battery chargers.Pre Lab Preparation:Discuss C data types for 8051Equipment: KEIL uVision5 compiler

GeniusPro540 / 840

8051 trainer


Oscilloscope

Procedure:a) Using software delay:

Write a C program to generate a square wave frequency on a pin of P2.

Now examine the frequency using the oscilloscope. Modify the count value to make it exactly 200Hz frequency.

Modify the above program to make Variable frequencies.

Modify the above program for different duty cycles. (25%, 75%)

Connect the 8 DIP switches on the trainer to P1. Then use the Switches to change the frequency and examine the Freq. oscilloscope.

If you have access to a Buzzer, connect it to pin P2.7 with a 74LS04 Inverter as a driver and see how the buzzer creates different sounds. You can also connect this pin to an Led on the trainer through the dip switch.b) Using 8051 timersThe following code is given to generate PWM using 8051 timers


Verify the above scenario using KEIL simulator.

Learning outcomes:

To be able to generate PWM signals of any duty cycle using software delays in 8051..

Questions:

Can this PWM signal be used to control the speed of a dc motor?

What is the maximum source sink current of an 8051 port pin.

Can we generate quadrature encoded signal in 8051?


(1 to 5)Remarks










Lab. 08Experiment title:Interfacing a DC motor to 8051


Speed of dc motors can be controlled by applying PWM signals of different duty cycles generated by 8051.PWM is applied to the dc motor through an H bridge. The motor can be directed to move forward, backwards, neutral e.t.c.Pre Lab Preparation:

Build a motor driver circuit using LM 298 and test it on a dc motor.

Equipment:

KEIL compiler Motor driver circuit

Dc motor

Oscilloscope

8051 trainer


G540

Procedure:

Using your 8051 trainer, build the circuit shown in Figure 17-6 (or 17-18 in older edition) of the textbook.

Truth table:

Then write and run a program to rotate it clockwise continuously. After making sure that above steps work, write and run the following:

Connect a buffered switch to P2.1 and use it for clockwise or counter clockwise. Use

P1.1=0 for CW and P1.1=1 for CCW. If you have set up serial 8051 communication, use

x86 PC to send letters R and L for clockwise and counter clockwise, respectively.

After making sure that Activity 1 works, write and run the following:

Use P1.7 and P1.6 to choose the speed of rotation.


Already mentioned aboveLearning outcomes:

To interface a DC motor to the 8051.

To write a program to control the speed and direction of DC motor rotation by the user.

Questions:

What is a use of Optoisolator ?

True or false. The DC motor speed is proportional to width of square wave applied to the DC.

Give the RPM for DC motor used in this Lab

What is the disadvantage of using CPL instruction for turning on and off the DC motor?

Explain the PWM Each student is required to perform the lab and submit the following Performa along with the lab report.1 = Unsatisfactory 2 = Fair 3= Satisfactory 4 = Very good 5= Excellent QuestionsRating

(1 to 5)Remarks










Lab. 09Experiment title:8051 interrupts programming

Programming the external hardware interrupts


If an interrupt source is triggered the CPU stops its work and run the interrupt service routine after which it again resumes with its task. If there are more then one interrupt sources CPU handles them according to the priority assigned. If too many interrupt sources are triggered DMA may be involved.Pre Lab Preparation:

Study 8051 interrupts from the book. Equipment:

8051 trainer 8051 KEIL Compiler Square wave generator Procedure: Write an 8051 program to get data from a single bit of P1.0 (connected to DIP SW) and send it to P2.7 (connected to LED) continuously while an interrupt can do the following: Connect the INT0 (or INT1) pin to a normally high debounce SW and any time the switch is pressed, a single LED is turned on. Write an 8051 program to get data from a single bit of P1.0 (connected to DIP SW) and send it to P2.7 (connected to LED) continuously while an interrupt will do the following: A square wave is connected to the INT0 (pin 3.2) and any time a H-to-L pulse comes in a single LED is turned on. The rate of "On" and "Off" is the rate of the square wave. In this activity you can also use INT1.Observations and Results:

Make all observations using an oscilloscope. Use KEIL simulator to see the results.Learning outcomes:

Learn to use 8051 external interrupt sources.

Learn to use 8051 timer interrupt sources.Questions:

Name all of the hardware interrupts in the 8051 and their vector table addresses.

On reset, INT0 (and INT1) are _________ (edge, level) triggered.

On reset, which interrupt has the highest priority?

True or False. There is only a single interrupt for the serial data transfer.Each student is required to perform the lab and submit the following Performa along with the lab report.1 = Unsatisfactory 2 = Fair 3= Satisfactory 4 = Very good 5= Excellent QuestionsRating

(1 to 5)Remarks










Lab. 10 Experiment title:a) Displaying a message using serial com port on hyper terminalb) Receiving bytes of data at the serial com and sending to the portIntroduction and Theory:

In serial communication data is sent bit by bit. It has wide applications in data communications.

8051 has an on chip serial com port. Serial communication between the 8051 and some other hardware take place under some protocol.Pre Lab Preparation:

Study and learn to use serial com registers in 8051. Study and analyze the code given below to use the serial com:

Equipment:

8051 KEIL Compiler. 8051 Trainer. Computer

Universal programmer.Procedure:Transmitting data: Write a program to send two different strings to the serial port. Assuming that SW is connected to pin P2.0, monitor its status and make a decision as follows:

a) SW = 0: send your first name at 4800 baud rate to hyper terminal.

b) SW = 1: send your last name at 9600 baud rate to hyper terminal.

Assume XTAL 11.0592MHz, 8bits, 1Stop bit.

Receiving data:

Write a program to receive bytes of data serially via the serial port and put them in P1. Set the Baud rate at 9600, 8bit data, and 1 stop bit. Use timer 1 for baud rate generation.


Message is successfully displayed on the hyper terminal. Serial Communication between the computer and 8051 is not possible without MAX232 in between. Analyze the voltage standards used by PC and 8051 for communication. Learning outcomes:

Learn to use serial com in 8051.Questions:

The 8051 TxD and RxD signals ________ (are, are not) TTL-compatible. In this lab, what is the role of the MAX233 (MAX232) chip? With XTAL=11.0592 MHz, what is the maximum baud rate for the 8051? Show how to achieve the maximum baud rate in Question 3. What is the role of TI and RI? True or false. The 8051 can transfer data in full-duplex. For full duplex, what are the absolute minimum signals needed between the 8051 Trainer and the x86 PC? Give their names.Each student is required to perform the lab and submit the following Performa along with the lab report.1 = Unsatisfactory 2 = Fair 3= Satisfactory 4 = Very good 5= Excellent QuestionsRating

(1 to 5)Remarks










Lab. 11Experiment title:8051 timer and serial com port interrupt programmingIntroduction and Theory:

Study timer interrupts from the book.Pre Lab Preparation:

Study the register configuration for serial interrupt programming from the book.Equipment:

8051 trainer

8051 KEIL Compiler Procedure:

Write an 8051 program to get data from a single bit of P1.0 (connected to DIP SW) and send it to P2.7 (connected to LED) continuously while an interrupt will do the following: One of the timers will toggle the PX.Y bit every 100 microseconds. Write an 8051 program to get data from a single bit of P1.0 (connected to DIP SW) and send it to P2.7 (connected to LED) continuously while an interrupt will do the following: A serial interrupt service routine will receive data from a PC and display it on one of the ports. (Either connect LEDs to this port to examine the data coming in or display the received data on an LCD).


Verify all steps by using Keil simulator.Learning outcomes:

To be able to use serial interrupts in 8051Questions:

Name all the Timer interrupts in the 8051 and their vector table addresses.

In timer mode 1, indicate when TF0 causes the interrupt.

In timer mode 2, indicate when TF0 causes the interrupt.

True or False. There is only a single interrupt for the both Timer 0 and 1.Each student is required to perform the lab and submit the following Performa along with the lab report.1 = Unsatisfactory 2 = Fair 3= Satisfactory 4 = Very good 5= Excellent QuestionsRating

(1 to 5)Remarks










Lab. 12Experiment title:Implementing switch de-bounce using Finite State MachineIntroduction and Theory:

Upon press or release, all mechanical switch contacts bounce The actual switch press has four possible states The desired output of the switch status variable should have two states (after debouncing)


Study the phenomena of switch debounce and periodic tasking from PONT C. Study FSM from Morris Mano. Design a finite state machine for the switch debounce by implementing a periodic task.Equipment:

KEIL compiler 8051 trainer

Procedure:

Create a new project Lab12 in folder Lab12. Complete the main.c file yourself. Inside the main() function write the code such that if button is pressed then LED flashes at 1 Hz, and if it is not pressed then LED flashes at 2 Hz. Build the project and download Lab12.hex file on 8051. Rewrite your program such that the de-bouncing feature is added into the button read function. Implement a periodic task for reading button input as a state machine using switch-case construct. Do not use for() or while() loops inside tasks to avoid blocking code. Observations and Results:

Already defined aboveLearning outcomes:

To design a finite state machine.Questions: What are the three states of a push button?

Write three benefits of Timed Cyclic Executive software architecture over a simple super-loop?

What are hazards of using for() loop or while() loop inside a periodic task()?


(1 to 5)Remarks









Additional Comments (if any):Lab. 13Experiment title:LCD interfacing with 8051Introduction and Theory:

A driver is to be written for an LCD as it is run by its own controller usually 8 pins for latching data, 2 for power supply, 4 pins for control, register selection and enable, 2 pins for contrast e.t.cPre Lab Preparation:

Study the data sheet for 2x16 LCD driven by Hitachi controller.

Equipment:

KEIL compiler LCD (2X16)

8051 trainer

Procedure:

Connect the LCD to your 8051 trainer as shown in section 12.1 of the textbook. Then compile and run the LCD driver program from the book or as provided by the instructor. Now, modify the above program to display you first name and last name, all on the same line Repeat Activity 1 while also putting the year you graduated from high school on the second line. When you run your program, the LCD should show (for example):

Khurram Ahmed

Graduated in 2012 Write an LCD program to display your last name on the first line and the current year on the second line. Both should be in the middle of the line.Observations and Results:


To understand the operation modes of an LCD. To interface and program an LCD.Questions:

How does the LCD distinguish data from instruction codes when receiving information at its data pin?

To send the instruction command code 01 to clear the display, we must make RS = ___.

To send letter 'A' to be displayed on the LCD, we must make RS = ____. What is the purpose of the E line? Is it an input or an output as far as the LCD is concerned?

When is the information (command code or data) on the LCD pin latched into the LCD?Each student is required to perform the lab and submit the following Performa along with the lab report.1 = Unsatisfactory 2 = Fair 3= Satisfactory 4 = Very good 5= Excellent QuestionsRating

(1 to 5)Remarks









Additional Comments (if any):Lab. 14Experiment title:Interfacing a keypad to an 8051Introduction and Theory:

Study the NxM matrix interfacing with 8051 and its driver from the book.Pre Lab Preparation:

The first step is to make a truth table for the keyboard. This truth table provides the row and column contacts by which a key is produced. Connect the ohmmeter leads, one to a row and one to a column terminal (lead) of the keyboard, and press the keys one at a time until you measure zero ohms. Repeat the process until all the keys are mapped.

Equipment:

8051 trainer

8051 Keil Compiler

4x4 keyboard or any N x M matrix keyboard

8 of 6.8K ohms resistors

.

Procedure:

After you have mapped your keypad set, connect the keypad to the 8051 as shown in Chapter 12 of the textbook. Write and run a program that scans your keyboard and displays any character pressed by the user on the LCD.

Your program must display keys 0 9 as numbers 0 9 on the x86 PC screen while keys 10, 11, 12, 13, 14, and 15 (or you might say 0A 0F in hex) are displayed as letters A, B, C, D, E, and F, respectively. You can modify and incorporate Program 121 of the textbook for your program.

Repeat Activity 2 for 4x4 keypad and use only a single port for both rows and columns.Observations and Results:

Already done aboveLearning outcomes:

To interface a 4x4 keyboard (keypad) to the 8051 trainer.

Questions:

What is the purpose of generating the truth table for a given keyboard? What is the purpose of grounding each row in keyboard interfacing?

What is the input to the microcontroller from column if no key is pressed?

True or false. In our N x M matrix keypad program we cannot press two keys at the same time.

In your program in Activity 2, how is the key press detected?

In your program in Activity 2, how is a key press identified?Each student is required to perform the lab and submit the following Performa along with the lab report.1 = Unsatisfactory 2 = Fair 3= Satisfactory 4 = Very good 5= Excellent QuestionsRating

(1 to 5)Remarks









Additional Comments (if any):Lab. 15Experiment title:Interfacing ADC804 to 8051Introduction and Theory:

In many applications we need to have multiple analog-to-digital converters. The ADC0804 IC is an 8-bit parallel ADC in the family of the ADC0800 series from National semiconductor devices. It works with +5volts and has a resolution of 8 bits. In the ADC0804, the conversion time varies depending on the clocking signals applied to the CLK IN pin, but it cannot be faster than 110usec.

Pre Lab Preparation:Students will build and test the interfacing circuit of ADC0804 with AT 89s52 before coming to lab. Connect the ADC804 to the 8051 Trainer. For the clock source of the ADC804, you can either use an external clock source (square wave TTL), which is preferable, or use the XTAL frequency from the 8051 XTAL as shown in Chapter 13. Make sure that you use at least three or four D flip-flops to bring down the frequency. Notice the following points when interfacing the 8051 Trainer to the ADC804.a) The ADC804 clock frequency is approximately 640 kHz at 5V.

b) Make CS =0 and send a low-to-high pulse to pin WR to start the conversion.

c) Keep monitoring the INTR pin. If INTR is low, the conversion is finished andwe can go to the next step. If INTR is high, keep polling it goes low.

d) After the INTR has become low, we make CS = 0 and send a high-to-low pulse to the RD pin to get the data out of the adc0804 IC chip.

Equipment:

8051 KEIL Compiler 8051 Trainer

ADC804

Potentiometer (10k)

TTL square wave and TTL square wave clock source

Procedure:

Connect a channel to potentiometer and LEDs of trainer to P1 pins.

Write a program to display data input from a channel connected to potentiometer on pins of P0. Examine the data displayed on LEDs. As the resistance of the potentiometer changes, the output should change, indicating the value of the analog input in binary.

Notice that the ADC outputs displayed on LEDs is between 0 to FFH where FFH is for a fullscale input. However, this must be converted to decimal and then to ASCII in order to be displayed on the LCD.Observations and Results:

Already mentioned aboveLearning outcomes:

To interface an ADC804 to the 8051Questions:

Indicate the direction of pin RD, WR and INTR from the point of view of the

ADC804. Give the steps for converting data and getting the data out of the ADC804. State the status of the INTR pin in each step. Give the role of signals INTR in selecting the ADC channel. In the ADC804 assume that Vref is connected to 2.56 V. Find the following.

a) step size

b) maximum range for Vinc) D7 D0 values if Vin = 1.2 V

d) Vin if D7 D0 = 11111111

e) Vin if D7 D0 = 10011100

In the ADC804 assume that Vref is connected to 2.7V. Find the following.

a) step size

b) maximum range for Vin

c) D7 D0 values if Vin = 1 V

d) Vin if D7 D0 = 11111111

e) Vin if D7 D0 = 11011101Each student is required to perform the lab and submit the following Performa along with the lab report.1 = Unsatisfactory 2 = Fair 3= Satisfactory 4 = Very good 5= Excellent QuestionsRating

(1 to 5)Remarks









Additional Comments (if any):Lab. 16Experiment title:Interfacing a stepper motor to an 8051


Stepper motors operate with precision with specific bit patterns applied to it as input.Pre Lab Preparation:

Learn to calculate the required step size for the stepper motor.

Learn different bit patterns applied to the stepper motor for operation

See the pin configuration and the tables for the stepper motor.

Study from any book Using your 8051 trainer, build the circuit shown in Chapter 15 of the textbook.Equipment: 8051 KEIL Compiler

8051 Trainer

Stepper motor

ULN2003 or ULN2803 Darlington driver chip. Procedure:Circuit connections: Write and run a program to rotate it clockwise continuously. Use the following steps to figure out the stepper motor leads.

1. Use an ohmmeter to measure the resistance of leads. This should identify the COM leads A through D winding leads.

2. The common wires are connected to the positive side of the motor's power supply. In

many motors, +5V is sufficient.

3. The four leads of the stator winding are controlled by four bits of the 8051 port (in this case P2.0 P2.3).However, since the 8051 lacks sufficient current to drive the stepper motor windings, we must use a driver such as the ULN2003 or ULN2803 to energize the stator. Change the delay to see the speed of rotation. write and run a program to rotate clockwise 180 degrees, stop for a second, then go counter clockwise to its original position.

write and run the following:

1. Connect a DIP switch of trainer to P2.1 and use it for choice of clockwise or counter clockwise. Use P2.1=0 for CW and P2.1=1 for CCW.

2. After the user has made a choice, the motor will rotate accordingly.

You can also use P2.7 and P2.6 to choose the degree of rotation.



To interface a stepper motor to the 8051.

To write a program to control the angle and direction of stepper motor rotation by the user.

Questions:

What is a step angle? Define steps per revolution.

If a given stepper motor has a step angle of 5 degrees, find the number of steps per rotation. Give the four sequences for counter clockwise if it starts with 10011001 (binary).Each student is required to perform the lab and submit the following Performa along with the lab report.1 = Unsatisfactory 2 = Fair 3= Satisfactory 4 = Very good 5= Excellent QuestionsRating

(1 to 5)Remarks










Pressed state

Not pressed state

Bouncing on press

Bouncing on release

If switch pressed after debounce period

If switch pressed after debounce period

If switch not pressed after debounce period

If switch not pressed after debounce period

Switch not pressed

Switch pressed

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Documents

Embedded System Lab Manual[1]