Abstract:
The system comprises at least one central processing (10, 12), a plurality of input/output terminals (14) and at least one control unit (16) having a plurality of ports (40, 42) each being connected to an input output terminal (14) for interfacing it with at least one central processing unit (10, 12). Each input/output terminal comprises a plurality of support logic means connected to one of the ports (40, 42) of the control unit (16), a buffer to each support logic means for storing data received from or to be transmitted to a central processing unit (10, 12), a text processor (38), a keyboard connected to the text processor (38) for effecting processing of link data and a printer and display (36, 48, 56) for outputting data and text character information. This structure allows the text processor (38) in the input/output terminal (14) to simultaneously, yet independently, emulate a display and printer normally associated with a host central processing unit.
Abstract:
The system comprises at least one central processing (10, 12), a plurality of input/output terminals (14) and at least one control unit (16) having a plurality of ports (40, 42) each being connected to an input output terminal (14) for interfacing it with at least one central processing unit (10, 12). Each input/output terminal comprises a plurality of support logic means connected to one of the ports (40, 42) of the control unit (16), a buffer to each support logic means for storing data received from or to be transmitted to a central processing unit (10, 12), a text processor (38), a keyboard connected to the text processor (38) for effecting processing of link data and a printer and display (36, 48, 56) for outputting data and text character information. This structure allows the text processor (38) in the input/output terminal (14) to simultaneously, yet independently, emulate a display and printer normally associated with a host central processing unit.
Abstract:
A communication adapter circuit (10) is connected to a processor through processor I/0 interface buses (12, 14). Data and control signals are provided through the buses (12, 14) to a timer circuit (18), a programmable peripheral interface circuit (20), an asynchronous and bisynchronous control circuit (22) and an SDLC/HDLC control circuit (24). Each of the control circuits (22, 24) includes parallel-to-serial and serial-to-parallel conversion circuitry. A clock select circuit (32) operates in conjunction with the timer circuit (18) and the programmable peripheral interface circuit (20) to establish a data transmission rate for the data flow through the adapter circuit (10). From the control circuits (22, 24) the data is transmitted through a modem interface bus (44) to a dual modem switch (56). From the switch (56) the data is transmitted to either an EIA RS 232 interface circuit (60) to a conventional modem or through a bus (64) to an internal modem. A phase locked loop circuit in the control circuit (24) generates a data clock signal on a line (33) for operation of the adapter circuit (0) in the bisynchronous protocol with a non-clock-generating modem.
Abstract:
A communication adapter circuit (10) is connected to a processor through processor I/0 interface buses (12, 14). Data and control signals are provided through the buses (12, 14) to a timer circuit (18), a programmable peripheral interface circuit (20), an asynchronous and bisynchronous control circuit (22) and an SDLC/HDLC control circuit (24). Each of the control circuits (22, 24) includes parallel-to-serial and serial-to-parallel conversion circuitry. A clock select circuit (32) operates in conjunction with the timer circuit (18) and the programmable peripheral interface circuit (20) to establish a data transmission rate for the data flow through the adapter circuit (10). From the control circuits (22, 24) the data is transmitted through a modem interface bus (44) to a dual modem switch (56). From the switch (56) the data is transmitted to either an EIA RS 232 interface circuit (60) to a conventional modem or through a bus (64) to an internal modem. A phase locked loop circuit in the control circuit (24) generates a data clock signal on a line (33) for operation of the adapter circuit (0) in the bisynchronous protocol with a non-clock-generating modem.
Abstract:
A communication adapter circuit (10) is connected to a processor through a data bus (12) and a control bus (14). Data and control signals are provided through the buses (12, 14) to a timer circuit (18), a programmable peripheral interface circuit (20), an asynchronous and bisynchronous control circuit (22) and an SDLC/HDLC control circuit (24). Each of the control circuits (22, 24) includes parallel-to-serial and serial-to-parallel conversion circuitry. A clock select circuit (32) operates in conjunction with the timer circuit (18) and the programmable peripheral interface circuit (20) to establish a data transmission rate for the data flow through the adapter circuit (10). From the control circuits (22, 24) the data is transmitted through a bi-directional serial line (44) to a dual modem switch (56). From the switch (56) the data is transmitted to either an interface circuit (60) to a conventional modem or through a line (64) to an internal modem.