Part A - Operating the 7490 counter

a. What is the function of pins 2 and 3?
    Pins 2 and 3 have the function called "reset to zero."

b. What happens when any of these pins (2 or 3) are raised to logic "1"?
    When either pin 2 or pin 3 is raised to logic "1," the output values are reset to 0000.

c. What is the function of pins 6 and 7?
    Pins 6 and 7 have the function called "reset to nine."

d. What happens when any of these pins (6 or 7) are raised to logic "1"?
    When either pin 6 or pin 7 is raised to logic "1," the output values are reset to 1001.

e. What is the purpose of connecting pin 1 to pin 12?
    The output from pin 12 is returned as input to pin 1 continuously.

f. What are the output pins?
    The output pins are pins 8, 9, 11, and 12.

Part B - Operating the 7442 BCD-to-decimal decoder

a. What are the input pins of the 7442?
    The input pins of the 7442 are pins 12, 13, 14, and 15.

b. How did you connect them to the 7490?
    Pin 8 of the 7490 is connected to pin 13 of the 7442. Pin 9 of the 7490 is connected to pin 14 of the 7442. Pin 11 of the 7490 is connected to pin 12 of the 7442. Pin 12 of the 7490 is connected to pin 15 of the 7442.

c. Describe the behavior of the LEDs connected to the outputs of the 7442.
    The LEDs light up consecutively, then repeats the cycle continuously.

Part C - Operating the 7447 seven-segment decoder

a. What are the input pins of the 7447?
    The input pins of the 7447 are pins 1, 2, 6, and 7.

b. How did you connect them to the 7490?
    Pin 12 of the 7490 is connected to pin 7 of the 7447. Pin 9 of the 7490 is connected to pin 1 of the 7447. Pin 8 of the 7490 is connected to pin 2 of the 7447. Pin 11 of the 7490 is connected to pin 6 of the 7447.

c. Describe the behavior of the LEDs connected to the outputs of the 7447.
    The LEDs display the decimal value of the binary input from the 7490.

Part D - General Observations

If you were to describe the experiment to your 12-year-old younger brother or sister, or to your mother, how would your description read?
    The 7490 counts continuously from zero to nine. At the same time, it sends out each decimal number in its equivalent binary value. These binary values are composed of four digits of ones and zeros. Each binary number is sent to the 7442, which makes each LED light up one after the other, depending on the number it has received. The same binary number is sent to the 7447, which is connected to the seven-segment LED. This LED will display the decimal value of the number it has received.