Abstract: A system operable with any number of different display truth table schemes. The system allows a user to select the truth table scheme and a driver circuit is used to drive either a single or pair of display elements. A binary application select detects a logic 0 if an application sense pin is left floating or is pulled low with a resistor. It detects a logic 1 if the application sense pin is pulled high with a resistor. The sense potential is such that all applications at the pin following reset, namely input or output with connected components will only detect a logic 1 when the pin is pulled high by a pull-up resistor. The output latched application is directed to a responsive circuit operable in a first condition when a logic 0 is detected, and a second condition when a logic 1 is detected. A binary select allows 2n different truth schemes to be selected where n is the number of pins used to select the application. When a first binary code is sensed, a first truth table is implemented.

Abstract: A communications inter-repeater circuit that includes an Attachment Unit Interface (AUI) port which can be selectively switched between a Media Attachment Unit (MAU) mode and a Data Terminal Equipment (DTE) mode. This selective change in the AUI allows for direct connection of Data Terminal Equipment (DTE) to the repeater without requiring a separate MAU. The determination of the mode for the AUI port is made by a selector. The selector may be a configuration sense pin whereon a selection potential is applied during reset of the repeater functions.

Abstract: An inter-repeater backplane employs both analog and digital circuitry to convey state machine information to adjacent repeaters thereby allowing seamless integration of multiple repeaters into a single hub without requiring additional drivers or external glue logic. A data path allows the passage of data between multiple repeaters on the inter-repeater backplane and an inter-repeater backplane enable allows individual repeaters to take control of the inter-repeater backplane data bus. An inter-repeater backplane driver enables external bus drivers which may be required in synchronous systems with large backplanes. An inter-repeater backplane clock is used to synchronize multiple repeaters on the inter-repeater backplane. Only two leads (IRCOL and IRCFS) are used to provide transmit and receive collision information. These two leads in conjunction with IRENA also indicate which repeater is receiving data.

Abstract: An inter-repeater backplane that may operate in either a synchronous or asynchronous mode for data transmission. The inter-repeater backplane includes a bus of electrical signal conductors coupled between repeaters for communicating electrical signals and data transmission mode detector for determining whether to transmit data synchronously or asynchronously. Data is recovered from a received data packet and is reframed for transmission across the inter-repeater backplane. According to which mode of data transmission is selected, the data is then retimed and transmitted across the backplane. In the synchronous mode of data transmission, the data is synchronized with the system clock. When the asynchronous mode of data transmission is selected, the data is transmitted asynchronously with respect to the system clock. In the asynchronous mode, the recovered data is timed with a clock signal associated with the transmitting repeater.

Abstract: A circuit for selecting different applications based upon the manner in which external elements are attached. The selection of the applications is controlled based on the potential detected at a pin immediately following reset. The voltage at a node of the application sense pin is compared with a reference voltage. The pin used to sense the application is used as a sense immediately after reset has occurred. After this it can function as either an output or an input. A flip-flop is connected such that the output of the application sense pin and the condition of reset is directed appropriately to the flip-flop. When the condition of not-in-reset is sensed, the flip-flop latches to a first condition or to a second condition based on the potential at the application sense pin. A binary select allows 2.sup.n different applications to be selected where n is the number of pins used to select the application. When a first binary code is sensed, a first application is implemented.