Communications

Communications provide the link between different devices such as PC's, handhelds, modems and printers. Some types of communications require a 'wire' (USB, serial, parallel), while others are 'wireless' - they just use the airwaves (Infrared, bluetooth; Wi-Fi). Each method of communication has distinct features that can be balanced when designing the optimal system for your company. A key decision is to select devices that use the same communications link - this may be the same for all devices, or different between different pairs of devices. For example, wired USB may be used to hotsync a handheld to a PC, while wireless bluetooth may be used to connect a handheld and printer.

Bluetooth is excellent for short range (30 feet) wireless communications. Bluetooth is ideally adapted for printing between a handheld and printer, because the two devices just need to be in the 'general area' of one another. Bluetooth also uses very little battery power - as little as 1% of wi-fi battery usage.

Some handhelds, such as the Palm Tungsten T3, have bluetooth included. Bluetooth expansion cards can be added to some handhelds.

By adding a parallel bluetooth adapter, just about any printer with a parallel port can become a bluetooth printer. There are not many 'native' bluetooth printers at this time, but they are getting more common as bluetooth becomes more widespread.

Infrared

Infrared light waves can be used to provide a 'line of sight' connection between two devices that are within three feet of one another.

Almost all handhelds have infrared capability.

Few printers have infrared capability. By adding a parallel infrared adapter, just about any printer with a parallel port can become a infrared printer.

While offering a wireless connection, the disadvantage of infrared is that it requires a direct 'line of sight' to be maintained between the two devices during the entire communication process.

Wi-Fi

Wi-Fi (IEEE 802.11) is wireless Ethernet; it provides an extension or replacement of wired networks for computing devices.

Wi-Fi is primarily used for higher speed wireless Ethernet access, while bluetooth wireless technology is used as a low cost cable replacement for connections between devices such as handhelds and printers.

USB

USB is the current 'standard' for wired connection between the PC and handheld hotsync cradle. USB hotsync speed can be several times faster than with a serial connection. This speed advantage is magnified when hotsyncs with multiple handhelds are required.

Just about all current handhelds use a USB port.

Because USB replaces all different kinds of serial and parallel port connectors with one standardized plug and port combination, many new PC's and printers have one type of port - USB.

A USB printer can become a wireless bluetooth printer by adding a USB bluetooth adapter to the printer.

Serial

Serial communications offer a 'tried and true' wired connection. Serial communications can travel great distances and are the 'standard' for communication between dialup modems.

For 'short range' wired connections, serial connections are quite slow compared to the other wired options (parallel and USB). For example, a serial hotsync will take longer than a USB hotsync.

Serial ports were on the original Palm units, and are still the primary port on Symbol SPT units.

Many business printers have an option to either include a serial port in the base configuration, or to add a serial port.

Parallel

While many printers have parallel ports, Palm units do not have parallel ports. There are some serial to parallel adapters, but they only work on older 'unidirectional' parallel port printers.

Because so many 'legacy' printers have parallel ports, the option to 'bluetooth enable' a printer with a bluetooth adapter is a very effective wireless upgrade to parallel port technology.