Time division multiplex communications system

Claim 1

A data communications system for transmitting data between a central transmitting station under computer control and a plurality of remote terminals comprising: a two conductor transmission medium interconnecting said remote terminals in series and said central station to first and last terminals in the series to form a serial transmission loop; said central station including; a data storage device under computer control for storing in sequential locations data to be transmitted in a predetermined number of communications channels, the data in each said channel including at least one multibit entity defining address, control and information for effecting communication between the central and one or more termInals, said predetermined number of communications channels and sequential locations being equal and substantially greater than one and substantially less than the number of series connected remote terminals, an output section for receiving in sequence the data associated with the channels from said data store and transmitting said channel data serial by bit to the first terminal in the serial loop and comprising, clock means for providing first timing pulses establishing a bit rate, second timing pulses establishing multibit information entity rate which is a function of the number of bits in an information entity, and third timing pulses establishing a channel rate which is a function of the number of entities in a channel, first means responsive to the third pulses for reading and making the data associated with sequential channels in the data store available for transmission, second means responsive to the second timing pulses for sequentially selecting the available entities associated with the available channel, and third means responsive to the first pulses for propagating the bits comprising each entity selected by the second means in series to the first terminal, an input section for receiving the serial data from the last terminal in the serial loop and for assembling said data in parallel entities comprising, means responsive to the data received from the last terminal for deriving a bit clock rate, means responsive to the data and the derived bit clock rate for storing and assembling the received serial data, means responsive to the bit clock rate for generating entity and channel rate pulses, and means responsive to the entity and channel rate pulses for transferring the assembled data to the same sequential location in the data store from which it emanated; and said terminals each including; means responsive to the data bits received from the previous connected unit in the series loop for deriving bit and entity rate pulses, storage means connected to the transmission medium for receiving at least as many data bits as comprise an entity under control of said bit rate pulses and transmitting said bits from the storage means via the transmission medium to the next connected unit in the series loop, and means responsive to said entity rate pulses and to the contents of the storage means for examining each said entity for detecting the address, control and information and for selectively altering the contents of the storage means at that time depending on the received data.

Claim 7

A method of communicating data between a central control station and a plurality of remote terminals connected in a series loop configuration with said central control station comprising the steps of: establishing at said central station a repetitive sequence of n time separated communications channels where n is substantially greater than 1 and substantially less than the total number of remote terminals connected in the serial loop communications network; generating at said central station for each of said channels a plurality of coded information carrying signals which include; a first part for identifying the start of the channel, a second part for selectively designating a single terminal from amongst the plurality of terminals connected in the serial loop which is to communicate via the channel or alternatively designating more than one terminal any one of which may appropriate a channel including a said alternative second part, and a third part for conveying data; transmitting the generated signals to the first terminal in the serial loop; at each of said remote terminals in said serial loop; storing and examining a finite number of the said coded information carrying signals before passing them on to a subsequent terminal in the loop to detect the first and second parts of the signals generated at the central, selectively accepting and inserting data in a channel bearing the specific terminal address in the said second part by selectively reading and altering the stored information carrying signals, and acquiring a communications channel when needed by detecting the said alternative second part and inserting in place thereof signals designating only the said terminal.

Claim 8

A method of communicating data between a central control station and a plurality of remote terminals connected in a series loop configuration with said central control station comprising the steps of: establishing at said central station a repetitive sequence of n time separated communications channels where n is substantially greater than 1 and substantially less than the total number of remote terminals connected in the serial loop communications network; generating at said central station for each of said channels a plurality of coded information carrying signals which include; a first part for identifying the start of the channel, a second part for selectively designating a single terminal from amongst the plurality of terminals connected in the serial loop which is to communicate via the channel or alternatively designating more than one terminal any one of which may appropriate a channel including a said alternative second part, and a third part for conveying data; transmitting the generated signals to the first terminal in the serial loop; at each of said remote terminals in said serial loop; storing and examining a finite number of the said coded information carrying signals before passing them on to a subsequent terminal in the loop to detect the first and second parts of the signals generated at the central, selectively accepting and inserting data in a channel bearing the specific terminal address in the said second part by selectively reading and altering the stored information carrying signals, and acquiring a communications channel when needed by detecting the said alternative second part and inserting in place thereof signals designating only the said terminal.

Claim 11

A method of communicating data between a central control station and a plurality of remote terminals connected in a series loop configuration with said central station comprising the steps of: establishing at said central station a repetitive sequence of n time separated communications channels, where n is substantially greater than 1 and substantially less than the total number of remote terminals connected in the serial communications loop; generating at said central station for each of said n time separated channels coded information carrying signals which include; a first part for identifying the start of the channel, a second part for selectively identifying a single remote terminal from amongst the plurality of remote terminals connected in the serial communications loop which is to communicate via the channel, and a third part for conveying information; transmitting the generated signals to the first terminal in the serial communications loop; at each of said remote terminals in said serial communications loop storing and examining a finite number of information carrying signals before passing them on to a subsequent terminal in the loop to detect the said first and second parts of the signals generated at the central, and selectively accepting and inserting data in a channel including the specific terminal address in the said second part by selectively reading and altering the information carrying signal.

Claim 12

A method of communicating data between a central control station and a plurality of remote terminals connected in a series loop configuration with said central station comprising the steps of: establishing at said central station a repetitive sequence of n time separated communications channels, where n is substantially greater than 1 and substantially less than the total number of remote terminals connected in the serial communications loop; generating at said central station for each of said n time separated channels coded information carrying signals which include; a first part for identifying the start of the channel, a second part for selectively identifying a single remote terminal from amongst the plurality of remote terminals connected in the serial communications loop which is to communicate via the channel, and a third part for conveying information; transmitting the generated signals to the first terminal in the serial communications loop; at each of said remote terminals in said serial communications loop storing and examining a finite number of information carrying signals before passing them on to a subsequent terminal in the loop to detect the said first and second parts of the signals generated at the central, and selectively accepting and inserting data in a channel including the specific terminal address in the said second part by selectively reading and altering the information carrying signal.

Claim 15

A method of communicating data between a central control station and a plurality of remote terminals connected in a series loop configuration with said central control station comprising the steps of: establishing at said central station a repetitive sequence of n time separated communications channels where n is substantially greater than one and substantially less than the total number of remote terminals connected in the serial loop communications network; generating at said central station for each of said channels a plurality of coded information carrying signals which include; a first part for selectively designating a single terminal from amongst the plurality of terminals connected in the serial loop which is to communicate via the channel or alternatively designating more than one terminal, any one of which may appropriate a channel including a said alternative first part, and a second part for conveying data; transmitting the generated signals to the first terminal in the serial loop; at each of said remote terminals in said serial loop; storing and examining a finite number of the said coded information carrying signals before passing them on to a subsequent terminal in the loop, and acquiring a communications channel when needed by detecting the said alternative first part and inserting in place thereof the signals designating only the said terminal.

Claim 16

A method of communicating data between a central control station and a plurality of remote terminals connected in a series loop configuration with said central control station comprising the steps of: establishing at said central station a repetitive sequence of n time separated communications channels where n is substantially greater than one and substantially less than the total number of remote terminals connected in the serial loop communications network; generating at said central station for each of said channels a plurality of coded information carrying signals which include; a first part for selectively designating a single terminal from amongst the plurality of terminals connected in the serial loop which is to communicate via the channel or alternatively designating more than one terminal, any one of which may appropriate a channel including a said alternative first part, and a second part for conveying data; transmitting the generated signals to the first terminal in the serial loop; at each of said remote terminals in said serial loop; storing and examining a finite number of the said coded information carrying signals before passing them on to a subsequent terminal in the loop, and acquiring a communications channel when needed by detecting the said alternative first part and inserting in place thereof the signals designating only the said terminal.