So far, we have explained about the CPU, the memory, and I/O functions.
Control (the fifth element) of the microcontroller is available only when connecting the CPU, memory, and I/O by wiring to allow signals to flow.
Figure 1 is an example showing the signal flow of a microcontroller.
Each function of the microcontroller is connected by many signal lines.
These signal lines are called "Bus line".
Figure 2 shows an example of the bus line.