4. There are two methods of sending streams of characters to the CD. Mention them and explain the difference, advantages, and disadvantages of each method.
5. Indicate the steps of each of the following activities:
a) Detect the key pressed.
b) Identify the key pressed.
7. If D3-D0=1101 is the data read from the columns, identify which column does the pressed key belong to.
8. If the rows are D3-D0=1011 and the columns are D3-D0=0111, identify which key is pressed?