1.

The return and retfie instructions perform very similar actions, but have a key difference. What is this difference and why is it needed?

2.

Modify the ISR code of Figure 10.10 to turn on an LED connected to RB2 when overrun of the software FIFO buffer is detected.

3.

In the logic diagram of Figure 10.2, what is the function of gate g1?

4.

In the logic diagram of Figure 10.2, what is the function of gate g2?

5.

In the logic diagram of Figure 10.2, what is the function of gate g3?

6.

In the logic diagram of Figure 10.2, what is the function of gate g4? (Hint: When IPEN = 0, you will also need to consider the function of gate g1.)

7.

Interrupt latency is the elapsed time between an interrupt occurrence, and execution of the ISR's first instruction. Propose a method for measuring this value using an oscilloscope and a program of your design.

8.

Write C code that implements the state chart of Figure 10.36. Use an approach similar to that used in Figure 10.15.

Figure 10.36: State chart for sample application.

9.

Assume an application heavily relies on software delay loops like DelayMS(), and requires that they be accurate. If the code also requires the use of interrupts, what can happen to the accuracy of the software delay loops? What can be done to preserve the accuracy? What would the...