What is the trunk modular principle of building a computer

The vast majority of modern PCs are built according to a certain scheme, called the computer architecture - a system of hardware (physical) and software (mathematics and logic) tools that allow you to program and perform the necessary tasks of the user. Computer architecture is external, reflecting the composition and interaction of the entire peripheral system, and internal, which contains the system of functioning of the components of the computer itself.

The basis of design and currently operating computers laid down a trunk-modular principle. The practical essence of this principle is that it is the user himself who can modernize the computer architecture, thanks to the compatibility and unification of computer components. The modular principle is supplemented with a backbone, or as it is also called - the bus principle of data exchange between modules and computer nodes. These two principles form one more principle of creating modern computers - the principle of open architecture. Physically, the principle of open architecture is realized by placing on the motherboard (system) board of various devices: processor, video and sound cards, memory devices (RAM and ROM). Also, the trunk-modular principle of building a PC, the theoretical foundations of which were formulated in the middle of the last century by J. Von Neumann, involves the following principles of software communication between computer components:

• Program control, which involves automatic execution of the processor commands and in a certain sequence;
• Homogeneity of memory, providing storage and commands and data in the same place;
• Addressability, according to which computer memory is created as a set of numbered cells, which the processor accesses.

The considered main-modular principle of building a computer allows creating a device configuration that is almost unique in terms of parameters (of course, within the technical parameters of its constituent parts and their compatibility) and provide a trunk method for transferring information between these parts. This exchange is carried out by using three different-sized tires (multi-wire lines). At the same time, the width of the bus depends on the length of the processor. The data bus is designed to provide information transfer in two directions: from the processor to another device of the computer and from this device to the processor.

The address bus provides access to the processor to the memory location of the device and operates only in a unidirectional mode - from the processor to the device.

The control bus transmits signals and commands that control the exchange of information and synchronize this exchange between different nodes of the computer. The physically considered trunk-modular principle of building a computer is realized thanks to the system bus, which, using the available slots (connectors), connects together the computer devices. The standards of system buses changed with the development of technology. Now the most common type of system bus is the PCI bus. The system bus, together with the devices connected to it, forms the trunk, which in its name mentions the trunk-modular principle of building a computer.

Individual modules of the computer are physically connected to this line with the help of controllers and adapters, their functioning as a program is provided by installing drivers that create the conditions for access of the operating system to the computer hardware system and back.

The standard set of modern computers includes:

• Video adapter (for display connection);
• Serial ports COM1 and COM2 (for connection of mouse and modem);
• Parallel port (for printer connection);
• Keyboard controller.

As the trunk-modular principle of building a computer suggests, other peripheral modules and devices can be connected to a computer by installing additional adapters.