This includes keyboards, cameras, mice, joysticks,modems, zip drives, floppy drives, printers, and scanners. In the last few years serial ports have almost disappeared from PCs, and USB ports have replaced them. There are thousands of industrial devices that have serial ports, and this change is causing problems.
Fortunately you may buy an inexpensive adapter that allows you to connect a USB port to a serial device. These devices work well, however they are only a stopgap measure. USB allows data to travel on the average of ten times the speed of the normal parallel port. Some systems generally desktops have non-powered USB ports on the front of the system and powered USB ports on the back. If experiencing issues, ensure the connection is a powered USB. To confirm Windows recognizes the device, use Device Manager.
If the driver is not found and installed by Windows, it will show up in "Other Devices". For further assistance, contact Technical Support. The A connector , shown in Figure 9 , is a flat connector that sends the data upstream.
The A connector is found on the back of the computer and the B connector is found on the external device. USB has iterated through several versions over the years. The original USB 1. USB 1. USB 2. However, USB 1.
USB 3. It is important to be familiar with the acceptable range of cable lengths for USB. High-speed devices support maximum cable lengths of 5 meters, while low-speed devices support a maximum cable length of 3 meters. These lengths can be extended with the use of powered hubs.
USB connections are used for any number of devices, including cameras, scanners, and barcode readers. It was intended as a high-speed, bidirectional Mbps serial transfer technology, for scanners, camcorders, and digital cameras. PC users, of course, wanted to take advantage of the higher speed of FireWire, so manufacturers created a special adapter card that would plug into the PCI slots common to PCs. Another advantage of FireWire is that it forms a peer-to-peer connection, meaning that any two FireWire devices can be plugged together directly and communicate with each other without a computer in the middle.
FireWire slots are now included on most motherboards. There are 4-conductor and 6-conductor FireWire implementations. A 6-conductor FireWire device can draw power through the cable just as in the case of USB; two power conductors are included, supplying a maximum of 30 volts and 1. Low power consumption devices, such as digital cameras, can draw power from a 6-conductor FireWire port; high power consumption devices, such as external hard drives, may require a separate AC power source.
A FireWire cable has either two or three pairs of twisted wires that carry data. Figure 10 displays 4-conductor and 6-conductor FireWire connectors. Figure 11 displays 6-pin FireWire ports. The recommended maximum length for a FireWire cable is 4. Figure 6-Pin FireWire Ports. After the release of USB 2. The full specification enables rates up to Mbps over optical connections.
Future versions of FireWire are expected to support rates up to 6. Bluetooth is one of the newest connection types and creates a wireless personal area network PAN. Printers, digital cameras, laptops, mobile phones, PCs, and video game consoles can connect and communicate with each other using Bluetooth. This technology uses an unlicensed, short-range radio frequency to provide a secure connection.
Hands-free audio connections in a car, as well as in-ear headsets, typically rely on Bluetooth technology. Figure 12 displays a Bluetooth earpiece for hands-free mobile phone communication. UART chip can convert parallel data to serial data and serial data to parallel data. Parallel port can transfer 8 bit or one byte via 8 wire. This interface port is very fast and generally used to connect printer or other devices.
Some types of parallel ports are given bellow. There are several types of parallel ports we use today. Some most popular of them is discussed bellow;. There was only one unidirectional parallel port in original IBM PC by which we can connect computer with printer. It can establish only one way communication. It is said bidirectional or extended parallel port.
The real communication between computer and printer can established by this port. It gives a transfer rate of 80 to Kbps. This is a special type of bidirectional port which gives a better performance after adding DMA Direct Memory Access technique.
EPP is a new specification which is called fast mode parallel port. It was developed by Intel, Xircom and Zenith data systems in It gives a better capability then conventional parallel port which has a speed as about ISA bus speed.
This is another high-speed parallel port. It was invented by both Microsoft and Hewlett-Packard in It also gives improved performance as EPP.
This two are serial Bus. These two-communication port gives very high speed than standard serial and parallel port. It can be the alternative to SCSI port. Besides better performance these ports can be connect with external devices. USB was designed to connect devices permanently with computer.
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