US 5497339 Portable apparatus for providing multiple integrated communication media
ABSTRACT – The present invention relates to a communication device for a personal digital assistant (PDA). The PDA mounts within the communication device and the communication device connects electronically to a serial port on the PDA. Through this single serial port, the communication device provides the user of the PDA with access to multiple communication media, such as a telephone modem, a Global Positioning System engine, a packet radio and a cellular telephone. Data from the PDA is directed to a decoder that routes the data to the appropriate communication medium, while data from the communication media are multiplexed onto the single serial interface of the PDA. The communication device also provides a pass-thru serial interface that allows other external devices to communicate directly with the serial port of the PDA. In addition, the communication device can upload software to the PDA that facilitates communications between the PDA and the communication device, and allows the PDA to control the operation of the communication device.
FIELD OF THE INVENTION
The present invention is in the field of portable communication devices for providing a computer with multiple integrated communication media, such as a phone modem, a cellular telephone, a packet radio and a Global Positioning System engine. In particular, the present invention relates to a portable multiple integrated communication device for a palm computer.
BACKGROUND OF THE INVENTION
Recent advances in the manufacture of integrated circuit components have allowed ever increasing functional capabilities to be performed by fewer integrated circuit components. This increased density of processing power in modern electronic equipment allows for the design of small, portable instruments with impressive processing capabilities. Advances in other technological areas, such as LCD displays, pen-based input devices and handwritten character recognition, have also contributed to a new generation of truly portable computers that are aptly described as palm computers or personal digital assistants (PDAs), but which have sufficient processing capabilities for numerous tasks. Examples of such PDAs include the Apple™ Newton™ and the Sharp™ Expert Pad™. These computers allow a user to take notes, store data, retrieve data, run certain application programs and interface with external devices, such as printers, modems or an Appletalk™ network.
SUMMARY OF THE INVENTION
The present invention connects to and interfaces with a PDA to dramatically increase the functional capabilities of the PDA. The present invention adds multiple integrated communication media to the resources currently available to the PDA, while maintaining a compact, portable size. For example, the combination of the present invention with a PDA can be used to place or receive a cellular telephone call or a land line telephone call, to transmit or receive packet radio data, to obtain three-dimensional location data from the Global Positioning System (GPS) and to send or receive data over a telephone cellular link or over a land line using a built in phone modem. These added communication features greatly enhance the utility of the PDAs. Instead of having a stand-alone PDA, isolated from other data sources, such as a person’s office computer network, the combined PDA and multiple integrated communication device provides a powerful processing device with convenient access to vast stores of information over a variety of possible media.
One aspect of the present invention involves a portable communication device. The communication device comprises first and second communication circuits providing first and second differing modes of communication, a first generic emulator coupled to the first communication circuit and a second generic emulator coupled to the second communication circuit, a first interface unit coupled to the first generic emulator and a second interface unit coupled to the second generic emulator, and an application program. The application program accesses the first interface unit to generate a first command to control the operation of the first communication circuit. The application program accesses the second interface unit to generate a second command to control the operation of the second communication circuit. The first interface unit communicates the first command to the first generic emulator. The second interface unit communicates the second command to the second generic emulator. The first generic emulator reformats the first command and communicates the first command to the first communication circuit. The second generic emulator reformats the second command and communicates the second command to the second communication circuit. The first communication circuit executes the first command and the second communication circuit executes the second command.
Additional aspects of the present invention will be apparent in the following detailed description of the invention.