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Data bus

Data bus definition

Data bus is a computer subsystem that facilitates the exchange of information between various components on a motherboard or system board or between separate computers. This involves moving information to and from the system's RAM or the CPU. Each one is constructed to deal with a certain number of data bits at the same time. Bandwidth is the measure of how much information a data bus can carry. Conventional data buses have a width of 32 bits. This indicates that 32 bits of data can be transferred through a data bus in a single second. Data buses built into modern computers can provide data paths with a bit depth of 64 bits or even 96 bits. Devices that operate at greater bitrates are being developed at the same time as data buses that can accommodate them.

Functions of a data bus:

  • A data bus transfers data between a computer's memory and its CPU, which operates as the device's “engine“.
  • Bus controllers manage component information interchange speed. CPU data always travels faster than other component data.
  • Data carried on a data bus might be parallel or serial.
  • Complex connections with multiple bits need a parallel bus. Parallel buses include PCI Express and SCSI.
  • Serial buses are simpler than parallel connections since they deliver and receive data over a single cable. Serial buses include USB and SATA.
  • An external data bus links the motherboard to peripheral devices, whereas a local one connects all its components.