Expansion Slots/Boards
Open/Closed architectures
Expansion Slots Expansion slots are receptacles inside a system unit that printed circuit boards (expansion boards)
- Open Architecture: This architecture is a system whose specifications are made public to encourage third-party vendors to develop add-on products for it. Most microcomputers adopt open architecture. They allow users to expand their systems using optional expansion boards.
- Closed Architecture: This is a system whose technical specifications are not made public. With a machine that has closed architecture, users cannot easily add new peripherals.
are plugged into. Computer buyers need to look at the number of expansion slots when they buy a computer, because the number of expansion slots decides future expansion. In microcomputers, the expansion slots are directly connected to the bus.
Expansion Boards
Expansion boards are also called expansion cards, controller cards, plug-in boards, adapter cards, or interface cards. Expansion boards are printed circuit boards that have many electronic components including chips. They are plugged into expansion slots.
Expansion boards are connected to peripherals through ports located on the edge of expansion boards. Expansion boards include memory expansion cards (e.g., SIMM), I/O controller cards (e.g., SCSI controller board), video display card, sound cards, communications cards, etc.
SCSI Controller Board: Small Computer System Interface (SCSI) controller card provides high-speed, parallel data transfer and multiple peripheral connections up to seven devices.
