SUMMARY
1. The bus systems (ISA, PCI, and USB) allow I/O and memory systems to be interfaced to the personal computer.
2. The ISA bus is either 8 or 16 bits, and supports either memory or I/O transfers at rates of 8 MHz.
3. The PCI (peripheral component interconnect) supports 32- or 64-bit transfers between the personal computer and memory or I/O at rates of 33 MHz. This bus also allows virtually any microprocessor to be interfaced to the PCI bus via the use of a bridge interface.
4. The PCI Express bus found on most computers is in the form of single lane or 16-lane ports.
The single lane port is interfaced to I/O devices, whereas the 16-lane port is interfaced to the video card replacing AGP.
5. A plug-and-play (PnP) interface is one that contains a memory that holds configuration information for the system.
6. The parallel port called LPT1 is used to transfer 8-bit data in parallel to printers and other devices.
7. The serial COM ports are used for serial data transfer. The Windows API is used in a Windows Visual C++ application to effect serial data transfer through the COM ports.
8. The universal serial bus (USB) has all but replaced the ISA bus in the most advanced systems.
The USB has three data transfer rates: 1.5 Mbps, 12 Mbps, and 480 Mbps.
9. The USB uses the NRZI system to encode data, and uses bit stuffing for logic 1 transmission more than 6 bits long.
10. The accelerated graphics port (AGP) is a high-speed connection between the memory system and the video graphics card.