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Central Processing Unit

This is the brain of most modern devices: PCs, laptops, servers, phones, etc.

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Processing Cycle

The CPU is composed of an ALU (Arithmetic Logic Unit), CU (Control Unit), as well as memory (usually in the form of cache). As the main component of a computer system, the CPU processes various instructions; these would stored in the form of lines of code within an executable.

In order to process these instructions, the CPU has to gather information from storage (like a HDD) or memory (in the form of RAM); this process is also known as fetch. During this phase, the CPU may receive both instructions (assembly code) and data.

Next, the CU decodes these instructions and data into a form that  the ALU can understand; for example, the operation mov, which moves a value into a memory location, would equate to various parts in the CPU’s circuitry to be used. In order the figure what circuitry is needed, the CU would decode the operation mov into the corresponding circuitry.

Lastly, the ALU executes the operation requested; depending on the CPU’s architecture, such x86/x64 and ARM, this step may be carried out over one cycle or multiple cycles, respectively.

Here is an example of the processing cycle in action, when performing an addition of 2 numbers:

The CPU gets to a byte in RAM that contains the command ADD 1 2 The CPU might do this process in 3 distinct cycles:

  1. MOV 1 A – The CU would set the memory location A in cache to the value 1.
  2. MOV 2 B – The CU would set the memory location B in cache to the value 2.
  3. ADD A B – The CU connects the memory locations A and B to the inputs of the ALU (which is configured into addition mode). The ALU then executes this operation and outputs a singular result into memory.


Arcade Game History

The first popular “arcade games” included early amusement-park midway games such as shooting galleries, ball-toss games, and the earliest coin-operated machines, such as those that claimed to tell a person’s fortune or that played mechanical music. The old Midways of 1920s-era amusement parks (such as Coney Island in New York) provided the inspiration and atmosphere for later arcade games. In the 1930s the first coin-operated pinball machines emerged. They lacked plungers or lit-up bonus surfaces on the playing field, and used mechanical instead of electronic scoring-readouts. By around 1977 most pinball machines in production switched to using solid-state electronics both for operation and for scoring.

Electro-mechanical games

In 1966, Sega introduced an electro-mechanical game called Periscope – an early submarine simulator and light gun shooter which used lights and plastic waves to simulate sinking ships from a submarine. It became an instant success in Japan, Europe, and North America, where it was the first arcade game to cost a quarter per play, which would remain the standard price for arcade games for many years to come. In 1967, Taito released an electro-mechanical arcade game of their own, Crown Soccer Special, a two-player sports game that simulated association football, using various electronic components, including electronic versions of pinball flippers.

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