Xonix – yeah that’s the name, I remember clearly… the city where Ra and I landed all of a sudden on a Friday evening. Before I realised what’s happening, Ra pulled my hand and started inching to the observation deck. They call it the Star Tower observation deck, said Ra. His voice exudes confidence. “Wow beautiful!” I said with excitement. The observation deck overlooks the city of Xonix. One of the best evening views I had so far. The first thing I noticed is the endless stream of cars, trucks, and trains carrying people and goods from one place to the other. These are some of the well defined surface routes like the expressways, bus terminus, railroads and airports.
Ra explained, “These are data buses that carry information between RAM and the CPU.” Just like how you have seen how traffic slows down when expressway lanes are blocked by stalled traffic, in this city, wider data buses that enable more data flow at the same time promote faster system performance.
After a while, we descended to the street level. We saw a local utility worker for a tour of underground Xonix. We came across a network of electric lines beneath the street carrying the energy needed to power the city. You can compare these to the power lines in the system bus, which transfer power from the motherboard’s connection to the power supply to the integrated circuits and expansion boards connected to the motherboard.
Go back to street level, and notice the traffic lights used both on city streets and on the entrance ramps to busy expressways, such as the Eisenhower and the Dan Ryan. Traffic stops and starts in response to the signals. Look at the elevated trains or at the Metra commuter trains and Amtrak intercity trains; they also move as directed by signal lights. These signals, which control the movement of road and rail traffic, can be compared to the control lines in the system bus, which control the transmission and movement of information between devices connected to the motherboard.
Finally, as you look around downtown, take a close look at the men and women carrying blue bags around their shoulders or driving electric vans around the city. As these mail carriers deliver parcels and letters, they must verify the correct street and suite addresses for the mail they deliver. They correspond to the address bus, which picks up information from the correct memory location among the gigabytes of RAM in computer systems and “deliver” new programs. It then changes back to the correct memory locations.
All of a sudden, I came out of my trance. There was fog all over. The streetlights faded into murkiness. “Hey it’s already late for home and I need to rush! Take me out of here…” I told Ra feeling nervous. Further down the street where the lights are quite dim, I can only see shapes, some I recognize, others quite amorphous, unidentifiable. A road quite elongated. But I guess we are out of Xonix – the wonder city.