12.2.4 Run-away Code

Run-away code can be caused by the MCU being operated outside its specification, faulty code or EMI issues. If a runaway code occurs, it is favorable to catch the issue as soon as possible. With a correct implementation of the PAC, the runaway code can potentially be stopped.

A graphical example showing how a PAC implementation will behave for different circumstances of runaway code in shown in Figure 12-3 and Figure 12-4.

In the example, green indicates that the command is allowed, red indicates where the runaway code will be caught, and the arrow where the runaway code enters the application. In special circumstances, like example 4 above, the runaway code will not be caught. However, the protection scheme will greatly enhance peripheral configuration security from being affected by runaway code.