CANNOT use arduino library functions except for serial.begin(), serial.println(), and serial.available(). Also how does the board setup look

Review the following sections of the datasheet to get generally familiar with the operations and registers that will be needed for the lab. - 16-Bit Timer Description - 17.2, Page 133 - Normal Mode Description - 17.1.9, Page 145 - Register Description - 17.11, Page 154 - Clock Select - 17.11.8, Page 157 - Prescalers - 18, Page 164 Procedure 1. Write a C program for the Arduino which will monitor the keyboard for inputs of A,B,C,D,E, F, and G. Depending upon which key was pressed use the timer to generate a square wave on PortB.6 of the ATmega2560 (Arduino Digital pin 12) of the appropriate frequency for the based on the table below. The note should last until another key is pressed, at which time the new note will be played. If the ' q ' key is pressed the note should stop playing. For debugging purposes, use of the Arduino Serial Library is permitted for this lab. Use the file serial_echo_example.ino as an example of serial 1/0. Your program must contain a function which takes the frequency as an input, and then configures and runs the timer. This function must work for all notes listed in the table. It does not have to work for all possible frequencies. div> serial_echo_example.ino