Wireless serial port transceiver
First Claim
1. An apparatus for transferring data between a source of information and a sink for information by a wireless linkage comprising:
- a first transceiver unit connecting to said source of information and having an address;
a second transceiver unit connecting to said sink for information and having an address;
a control on each of said first and second units for placing them into a first linkage mode;
a handshake protocol within each of said first and second units, placed into operation when the units are in said first linkage mode, which causes them to continuously attempt to handshake with another transceiver unit and exchange addresses by one broadcasting its address and by the other responding with its own address;
said first and second units, following the successful execution of said address exchange handshake between them, placing themselves into a data communications mode where each communicates exclusively with the other and where said first and second units remain in said data communications mode indefinitely; and
said units thereafter wirelessly transferring data in the form of packetized, error correctable, addressed data packets, and also transferring addressed acknowledgments of successful receipt of such data packets, to transfer data in an error-free manner between said source and said sink.
1 Assignment
0 Petitions
Accused Products
Abstract
A pair of compact, energy-efficient, intelligent, wireless transceiver units are designed to replace the cable that interconnects a portable bar-code scanner, keyboard, and display or other host to a portable bar-code printer or the like. When reset, the units exchange linkage packets and thereby exchange addresses. Thereafter, the two units communicate in an error-free fashion with each other, even in the presence of noise and interference, by exchanging addressed packets containing error detection information. Alternate transmission frequencies are selected when transmissions cannot be received at one frequency. The host unit may maintain independent linkages with multiple printers or the like, with a switch on the host unit selecting the desired printer. Power usage is minimized by shutting down transmitters, receivers, serial port drivers, and microprocessors whenever possible, and for extended periods when data is not being transmitted.
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Citations
33 Claims
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1. An apparatus for transferring data between a source of information and a sink for information by a wireless linkage comprising:
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a first transceiver unit connecting to said source of information and having an address; a second transceiver unit connecting to said sink for information and having an address; a control on each of said first and second units for placing them into a first linkage mode; a handshake protocol within each of said first and second units, placed into operation when the units are in said first linkage mode, which causes them to continuously attempt to handshake with another transceiver unit and exchange addresses by one broadcasting its address and by the other responding with its own address; said first and second units, following the successful execution of said address exchange handshake between them, placing themselves into a data communications mode where each communicates exclusively with the other and where said first and second units remain in said data communications mode indefinitely; and said units thereafter wirelessly transferring data in the form of packetized, error correctable, addressed data packets, and also transferring addressed acknowledgments of successful receipt of such data packets, to transfer data in an error-free manner between said source and said sink. - View Dependent Claims (2, 3, 4)
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5. A method for establishing a wireless linkage between a source and a sink for information comprising the steps of:
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placing the source and the sink into a first linkage mode where each is seeking out a linkage partner; while both are in the linkage mode, causing the source and sink to continuously attempt to handshake with each other through an exchange of addresses between said source and sink; having said source and sink, following a successful address exchange handshake, switch into a second data communications mode where each communicates by address exclusively with the other and where said source and said sink then remain in said data communications mode indefinitely; and while both are in the data communications mode, having the source send addressed, packetized, error detectable data packets to the sink, and having the sink return addressed acknowledgments of successful packet receipt. - View Dependent Claims (6, 7, 8)
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9. A wireless link designed to replace an industry-standard transmission cable having first and second signal connectors, comprising:
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first and second transceiver units having respectively first and second signal connectors; a control on each unit for placing the unit into a first linkage mode; a handshake protocol within each unit placed into operation when the unit is in said first linkage mode which enables one of a pair of such units to broadcast its address and which enables the other of the pair of such units to capture the broadcast address and to return its own address; a control within each unit when in said first linkage mode that senses the successful completion of an exchange of addresses between two such units in linkage mode and that thereafter places the units which exchanged addresses into a second data transmission mode, wherein they can send addressed data packets to each other; a data exchange protocol within each pair of units, when the units are address-linked in said second data transmission mode, which causes them to receive data from the signal connector, packetize the data, send the packetized, addressed, error detectable packets via radio to the other unit, receive such addressed packetized data, check the data for errors, acknowledge an accurate transmission by sending a return-addressed acknowledgement packet to the other unit, and present the data to the signal connector. - View Dependent Claims (10, 11, 12, 13, 14)
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15. A pair of identical wireless transceivers designed to be used in pairs as a wireless transmission linkage and designed to conserve power, each comprising:
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a power supply; a transmitter; a receiver; a data port; a programmed microprocessor having facility for data input and output, connecting to said transmitter, receiver, data port, and power supply, and programmed to transfer data between said data port and said transmitter and receiver, packetizing data presented to said transmitter with address and error detection data and unpacketizing and error checking data received from said receiver, discarding erroneous data received from said receiver and requesting its retransmission; means controlled by said programmed microprocessor for powering down said transmitter when not transmitting, said receiver when not receiving, and said data port when not transferring; means for causing each unit to initially exchange addresses with another unit and thereafter communicate only with said other unit, thereby forming a linked pair of units; and means actuated during idle periods, for powering up the receiver in one of a pair of units only periodically, at certain times, and timing means arranging for the other of such a pair of units to commence transmitting data packets only at such times. - View Dependent Claims (16)
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17. A wireless data switch interconnecting a source of data with multiple sinks of data comprising:
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a first unit connecting to said source and arranged to receive information from said source; for each said sink, a second unit connecting to said sink and arranged to present information to said sink; each said unit having a transmitter and a receiver and a data port for connecting to said source or sink; switch means in said first unit for selecting one of several possible sinks of information; means associated with each said second unit including an address enabling it to broadcast said address when placed into a first linkage state and, later, to receive addressed data packets when placed into a second data transfer state; and means associated with said first unit, when said switch means is in any given position, for first entering a linkage state continuously seeking and attempting to accept the address one of said second units that is also in said first linkage state and for thereafter, following a successful acceptance of a selected second unit'"'"'s address, whenever said switch means is in that same position, entering a data transfer state wherein source data is sent in addressed packets exclusively to said selected one of said second units for presentation to said associated sink, and thereafter both said first unit (whenever said switch means is in that same position) and said selected one of said second units remain in said data transfer state indefinitely; whereby the source may be linked by wireless addressed linkage to plural sinks and may thereafter send data to any one of them under control of said switch. - View Dependent Claims (18, 19)
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20. An apparatus for transferring data between a source of information and a sink for information by a wireless linkage comprising:
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a first battery powered transceiver unit connecting to said source of information and having an address; a second battery powered transceiver unit connecting to said sink for information and having an address; a control on each of said first and second units for placing them into a first linkage mode; a handshake protocol within each of said first and second units, placed into operation when the units are in said first linkage mode, which causes them to continuously attempt to handshake with another transceiver and exchange addresses by one broadcasting its address and by the other responding with its own address; said first and second units, following the successful execution of said address exchange handshake between them, placing themselves into a data communications mode where each communicates exclusively with the other and where said first and second units remain in said data communications mode indefinitely; said units thereafter wirelessly transferring data in the form of packetized, error correctable, addressed data packets, and also transferring addressed acknowledgements of successful receipt of such data packets, to transfer data in an error-free manner between said source and said sink; and said units conserving power by shutting down transmitter, receiver, and connector components when not conveying or waiting for information. - View Dependent Claims (21, 22, 23)
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24. A wireless link designed to replace an industry-standard transmission cable having first and second signal connectors, comprising:
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first and second transceiver units having respectively first and second signal connectors, at least one of said transceiver units is being battery powered and conserving power by powering down its transmitter and receiver and connector when not conveying or awaiting information; a control on each unit for placing the unit into a first linkage mode; a handshake protocol within each unit placed into operation when the unit is in said first linkage mode which enables one of a pair of such units to broadcast its address and which enables the other of the pair of such units to capture the broadcast address and to return its own address; a control within each unit when in said first linkage mode that senses the successful completion of an exchange of addresses between two such units in linkage mode and that thereafter places the units which exchanged addresses into a second data transmission mode, wherein they can send addressed data packets to each other; a data exchange protocol within each pair of units, when the units are address-linked in said second data transmission mode, which causes them to receive data from the signal connector, packetize the data, send the packetized, addressed, error detectable packets via radio to the other unit, receive such addressed packetized data, check the data for errors, acknowledge an accurate transmission by sending a return-addressed acknowledgement packet tot he other unit, and present the data to the signal connector. - View Dependent Claims (25, 26, 27, 28)
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29. A pair of identical wireless transceivers designed to be used in pairs as a wireless transmission linkage and designed to conserve power, each comprising:
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a battery power supply; a transmitter; a receiver; a data port; a programmed microprocessor having facility for data input and output, connecting to said transmitter, receiver, data port, and battery power supply, and programmed to transfer data between said data port and said transmitter and receiver, packetizing data presented to said transmitter with address and error detection data and unpacketizing and error checking data received from said receiver, discarding erroneous data received from said receiver and requesting its retransmission; means controlled by said programmed microprocessor for powering down said transmitter when not transmitting, said receiver when not receiving, and said data port when not transferring; means for causing each unit to initially exchange addresses with another unit and thereafter communicate only with said other unit, thereby forming a linked pair of units; and means actuated during idle periods, for powering up the receiver in one of a pair of units only periodically, at certain times, and timing means arranging for the other of such a pair of units to commence transmitting data packets only at such times. - View Dependent Claims (30)
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31. A pair of wireless transceiver units that can interconnect a source of information with a sink for information, said source and said sink generating flow control signals, said units comprising:
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within each unit, means for transmitting and receiving at either of two or more frequencies; within a first unit connected to said source, means for accepting information from said source, packetizing the information with the address of the other unit and error detection information, and transmitting said packets at a first frequency using direct carrier waive modulation by the binary data; within a second unit interconnected to a sink, means for receiving and error checking said packets at said first frequency, responding with an acknowledgement or negative acknowledgement packet in accordance with the presence or absence of errors, and sending error-free data to said sink; within said first unit, means for responding to a negative acknowledgement packet by retransmitting the packet most recently sent; means within both said units for shifting transmission and reception frequencies after an excessive number of successive negative acknowledgement packets have been sent by said second unit; and wherein said units communicate said flow control signals between the source and sink to achieve overall data flow control.
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32. A pair of wireless transceiver units that can interconnect a source of information with a sink for information comprising:
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within each unit, means for transmitting and receiving at either of two or more frequencies; within a first unit connected to said source, means for accepting information from said source, packetizing the information with the address of the other unit and error detection information, and transmitting said packets at a first frequency using direct carrier wave modulation by the binary data; within a second unit interconnected to a sink, means for receiving and error checking said packets at said first frequency, responding with an acknowledgement or negative acknowledgement packet in accordance with the presence or absence of errors, and sending error-free data to said sink; within said first unit, means for responding to a negative acknowledgement packet by retransmitting the packet most recently sent; means within both said units for shifting transmission and reception frequencies after an excessive number of successive negative acknowledgement packets have been sent by said second unit; and if successive negative acknowledgement packets continue to be sent following a change in frequency, or if neither acknowledgement nor negative acknowledgement packets are received at appropriate times, and error indication is given to signal a failure of communication.
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33. A pair of wireless transceiver units that can interconnect a source of information with a sink for information comprising:
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within each unit, means for transmitting and receiving at either of two or more frequencies; within a first unit connected to said source, means for accepting information from said source, packetizing the information with the address of the other unit and error detection information, and transmitting said packets at a first frequency using direct carrier wave modulation by the binary data; within a second unit interconnected to a sink, means for receiving and error checking said packets at said first frequency, responding with an acknowledgement or negative acknowledgement packet in accordance with the presence or absence of errors, and sending error-free data to said sink; within said first unit, means for responding to a negative acknowledgement packet by retransmitting the packet most recently send; means within both said units for shifting transmission and reception frequencies after an excessive number of successive negative acknowledgement packets have been sent by said second unit; if successive negative acknowledgement packets continue to be sent following a change in frequency, or if neither acknowledgement nor negative acknowledgement packets are received at appropriate times, an error indication is given to signal a failure of communication; and reset switches which, when actuated on both units at about the same time, cause the two units to re-initiate their efforts to communicate.
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Specification