[SOLVED] EIE373 Microcontroller Systems and Interface Laboratory Exercise 1 Introduction to AVR C/C

Department of Electrical and Electronic Engineering

EIE373 Microcontroller Systems and Interface

Laboratory Exercise 1: Introduction to AVR

(Deadline: Check the course information)

Objectives:

1.   To familiarize students with the use of an AVR microcontroller.

2.   To develop C programs under the Arduino platform.

Equipment:

Atmel Studio and Arduino IDE (software; check the version in the course information) The Arduino Starter Kit (hardware)

 

Important Notices:

1.   Download the ATmega328p datasheet from the Blackboard before doing the laboratory exercises.

2.   You can buy a kit and bring it to the lab sessions or leave your student identity card in the box beside the kits to borrow one kit box. You get the card back when you return the box. Note that you must return the box five minutes before the end of the laboratory sessions.

3.   All components you need can be found in the kit box.

Introduction:

This experiment introduces some simple applications of an AVR microcontroller to perform arithmetic and I/O operations. Students develop C programs and build simple electronic circuits for such simple applications.

Atmel Studio is the integrated development platform (IDP) for developing and debugging Atmel AVR microcontroller (MCU) applications. It gives you a seamless and easy-to-use environment to write, build, and debug your applications written in C/C++ or assembly code. Atmel  Studio  supports  all  8-  and  32-bit  AVR  MCUs  and  connects  seamlessly  to  Atmel debuggers and development kits.

The Arduino Start Kit teaches you the basics of using the Arduino hands-on. You will learn by building several creative projects. The kit includes a selection of the most common and useful electronic components.

Procedure:

Section A: Create your first simple application

1.   Open Atmel Studio: Double-click the icon of Atmel Studio.

2.    Change the mode from “Standard” to “Advanced” .                             

 

3.   Go to the main menu. Select “Tools” → “External Tools” . Type in “Arduino Uno” in the

field “Title”. Type in the following paths into the fields “Command” and “Arguments” :

C:Users??AppDataLocalArduino15packagesarduinotoolsavrdude6.3.

0-arduino17/bin/avrdude.exe

C”C:Users??AppDataLocalArduino15packagesarduinotoolsavrdude6. 3.0-arduino17/etc/avrdude.conf” -v -V -patmega328p -carduino “-PCOM4” – b115200 -D “-Uflash:w:$(ProjectDir)Debug$(TargetName).hex”:i

Note  that  ?? is  your  username  (e.g.,  22123456d).  These  two  paths  are  in  the  text  file ArduinoUno.txt, which can be found in the zip file “EIE3373 Course Materials.zip”, which can be  downloaded  from  Blackboard.  Read  “Important  information”  on  Page  4  before downloading your program to your Arduino.

Atmel Studio and Arduino IDE are freeware, and you can download them from the Internet to your computer. You can follow the steps below to find the “Command” and “Argument” paths using the Arduino IDE on your computer:

1.   Open the Arduino IDE: Launch the Arduino IDE on your computer.

2.   Access the Blink Example: Go to File → Examples → 01.Basics → Blink.

3.   Select the Arduino Uno Board: Go to Tools → Board → Arduino Uno.

4.   Enable   Detailed  Upload   Output:   Got  to   File →   Preferences.   In   the Preferences window,  check  the  box   labeled  “ Show  verbose  output during: upload”. Click OK to save the settings.

5.   Upload the Blink Sketch: Click the Upload button (the right arrow icon) to compile and upload the Blink sketch to your Arduino Uno.

6.   Check the Output Window: Observe the output window at the bottom of the Arduino IDE after uploading. Look for some lines similar to the following texts (usually around line 3):

“C:UsersYourUsernameAppDataLocalArduino15packagesarduinotools avrdude6.3.0-arduino17/bin/avrdude” “-

CC:UsersYourUsernameAppDataLocalArduino15packagesarduinotools

avrdude6.3.0-arduino17/etc/avrdude.conf” -v -V -patmega328p – carduino “-PCOM4” -b115200 -D “-

Uflash:w:C:UsersYourUsernameAppDataLocalTemparduinosketchesF3 4549723ED32139E374C1C89CFACE38/Blink.ino.hex:i”

7.   Extract the Command and Argument: Copy the lines to a text file and modify its

contents to create the command and argument paths. The lines:

“C:UsersYourUsernameAppDataLocalArduino15packagesarduinotools avrdude6.3.0-arduino17/bin/avrdude” “-

CC:UsersYourUsernameAppDataLocalArduino15packagesarduinotools avrdude6.3.0-arduino17/etc/avrdude.conf” -v -V -patmega328p –

carduino “-PCOM4” -b115200 -D “-

Uflash:w:C:UsersYourUsernameAppDataLocalTemparduinosketchesF3 4549723ED32139E374C1C89CFACE38/Blink.ino.hex:i”

Command path:

C:UsersYourUsernameAppDataLocalArduino15packagesarduinotools avrdude6.3.0-arduino17/bin/avrdude.exe

Argument path:

C”C:UsersYourUsernameAppDataLocalArduino15packagesarduinotool savrdude6.3.0-arduino17/etc/avrdude.conf” -v -V -patmega328p –

carduino “-PCOM4” -b115200 -D “-

Uflash:w:$(ProjectDir)Debug$(TargetName).hex”:i

Replace YourUsername with your actual username in the file paths.

Important information:

a.   Note that “COM4” in the above path shows the port the Arduino Uno plugs into your computer. Thus, later, when you plug in the Arduino Uno to your computer, you need to check whether the port is “COM4” or not (Double click the icon “Computer” and Select “Properties” → “Device Manager” → “Ports”. Check the position of the port for the Arduino Uno). You may need to change the port number if it is not “COM4” .

b.   Moreover,you may goto Blackboard to download the text file “ArduinoUno.txt” in the course material (in the folder “AVR Programming Materials”). This file stores these two paths. Then, you can copy and paste them into such two fields.

After that, click the checkboxes “Use Output window” and “Prompt for arguments” and then click the button “OK” . When you finish the setting, a new field, “Arduino Uno” is created under the menu item “Tools”. Note that the above setting must go through once you have opened Atmel Studio for the first time.

 

4.   Go  to  the  main  menu  and  create  a  new  project.  Then  select  “C/C++”  and  “GCC  C Executable Project” to create anew project. Type in the project name “Lab1A”. After that, select “ATmega328p” .

 

Note that the I/O ports of the AVR microcontroller are bit-accessible, but the AVR C compiler does not support this feature. Thus, you should use a mask to set, clear, and check some bits in the I/O ports.

 

5.   Type in the following program into “Lab1A.c” .

#include <avr/io.h>

int main(void) {

DDRD = 0xFF; while(1)

{

PORTD = 0x55; }

}

6.   Go to the main menu. Select “Build” → “Build Solution” to compile the program.

7.   Build the circuit below on the Arduino Uno and the breadboard. Check the pinout diagram in the appendix or some files in the course material.

8.   Go to the main menu. Select “Tools” → “Arduino Uno” to burn the program into the ArduinoUno. You should see some LEDs are on. If it does not work, check the “Important

Information” below.

Important information:

Note that you should remove any connections topin 0 (RX) and pin 1 (TX) of the Arduino Uno  before  you  burn  your  program  into  it;  otherwise,  your  program  may  not  burn successfully.

9.   Repeat the above steps, but this time, Port D is toggled between 0x55 and 0xAA with a one to two-second time delay. It would be best to use looping to generate the delay and set the optimization level to the first one (level zero). Show the calculation of how to generate the delay. Note that the clock frequency of the Arduino Start Kit is  16 MHz. When your program works correctly, all LEDs connected to Port D are flash.

Section B: Simple applications

1.   Connect a switch to PB0; the pin diagram is shown in Step 7 of Section A.   Connect an LED to the switch. When the switch is pressed, the LED is on. When the switch is released, the LED is off. Connect an LED to PD2. When the switch is pressed, the LED in PD2 is on. When the switch is released, the LED in PD2 is off. You may connect an LED serially with R1 to check whether the circuit to connect the switch is correct.

2.   Use the circuit in Section A and the connection in Step 1. There are two states in the switch: States 0 and 1. When it is in State 0, all LEDs connected to Port D are off. When it is in State 1, all LEDs are on. At the beginning, the switch is in State 0. When (1) the current state is 0 and (2) the switch is pressed and then released, it goes from State 0 to State 1. When (1) the current state is 1 and (2) the switch is pressed and then released, it goes from State 1 to State 0.

Demonstrate Section A (Steps 8 and 9) and B (Steps 1 and 2) to our student helpers.

Instructions:

1.   You are required to demonstrate your programs to our student helpers.

2.   Zip all programs (including the whole projects) in Sections A and B to a single file. Please submit it to Blackboard.

3.   Deadline: Check the course information.