A bar code works in much the same way as an ordinary flashlight, by reading the reflected light from a surface, This process begins when a device directs a light beam through a bar code. The device contains a small sensory reading element. The sensor detects the light being reflected back from the bar code, and converts it to electrical energy, and in then converted to into data.
The benefits of implementing bar codes for automated data collection are very simple: speed and accuracy. It has been proven that entering barcode data is approximately 100 times faster and more accurate than a manual keyboard entry, which in turn increases the accuracy, efficiency and productivity of any facilities operations.
The PDT, or Portable Data Terminal, was specifically designed to bring the computer to the bar code, particularly to address the jobs such as warehouse management and inventory control. A fully programmable handheld computer is necessary in such instances.
Selecting the mode of communications is very important in determining what end result your operation is attempting to achieve. Collected data can be transferred back to the host in one of two ways.
- A radio frequency communication link, providing an online, real time data uplink. This often requires a more complex connection to the host which will result in a more costly implementation. When online real time data transfer is required, RF is the method of choice.
- Batch data collection is a simpler and easier process. In this method data is collected in small batches and transferred from the portable into the host computer by a serial cable connection.
- Programming – The operating system of a PDT determines the method of programming used. Proprietary operating systems usually require knowledge of the proprietary language. Other units may use a common operating system such as DOS, MS Windows, and now Windows CE … allowing for programming with a more common language base such as Visual Basic, Basic or C.