prelab6.txt

1. You will need to familiarize yourself with the C functions used to
communicate with the I2C device. Look at the following functions in the Linux
source file i2c-dev.h and describe what each one does.

a. i2c_smbus_read_byte(int file)

    returns 1 byte of the file, or -1 if it couldn't access it

b. i2c_smbus_write_byte(int file, __u8 value)

    writes the given value to the given file

c. i2c_smbus_write_byte_data(int file, __u8 value, __u8 command)

    sets data byte to given value, and accesses the smbus using the given command 

2. For the second part of the lab, you will need to use the QT framework to
implement a "painting" program using the Wii Nunchuk.  Read the Qt
documentation provided on the class website for the QPainter, QPen and QPoint
classes. Define the following functions:


a. For QPainter:
    void QPainter::setPen ( const QPen & pen )
        Sets the painter's pen to be the given pen.
        The pen defines how to draw lines and outlines, and it also defines the text color.
    void QPainter::drawLine ( const QLineF & line )
        Draws a line defined by line. example: 
            QLineF line(10.0, 80.0, 90.0, 20.0);
            QPainter(this);
            painter.drawLine(line);

b. For QPen:
    void QPen::setColor ( const QColor & color )
        Sets the color of this pen's brush to the given color.
c. For QPoint:
    void QPoint::setX ( int x )
        Sets the x coordinate of this point to the given x coordinate.
    void QPoint::setY ( int y )
        Sets the y coordinate of this point to the given y coordinate.

3. Read the AIMB 213 User Manual with focus on the GPIO Port pins and the JFP
1 & JFP 2 Port pins and the Wii Nunchuk guide from the class website. Define
the following terms:

    GPIO  -- General Purpose Input/Output

        pins that you can set to either input or output depending on what you
        want them to do

    SMBus -- System Management Bus

        simple, two-wire bus derived from I^2 C, often used for communicating
        with a device's power or battery

    I2C -- Inter-Integrated Circuit

        two-wire interface for slow communication between a motherboard and
        its peripherals. the serial protocol can handle multiple masters, and 
        slave addresses have to be licensed from the NXP corporation for a fee.