PERSONAL COMPUTER ATTACHMENT TO HOST SYSTEM DISPLAY STATIONS

摘要

A personal computer attachment for a display station that communicates with a host computer (48) and includes a CRT (38), a regeneration buffer (42), a keyboard adapter (46), a feature bus (44) and a keyboard (12) attached thereto a personal computer system unit which includes a system bus, a microprocessor, memory, a keyboard adapter and I/O interface connected to the system bus supporting floppy diskette drives (16) and a printer (18). A display adapter (26 or 28) is connected to the I/O interface. An analog input switch (52) is disposed between the buffer (42) and the analog circuits driving the CRT (38) and has a second input from adapter (26 or 28) and is controlled from the keyboard (12) to selectively supply image data from buffer (42) or adapter (26 or 28). An attachment adapter (36) includes an input/output interface (54), a switch control (56), a two-way keyboard adapter (58) and a feature bus adapter (60) and mates with the I/O interface of the personal computer system unit via which its components communicate with the system bus of the personal computer system unit. The keyboard (12) is connected to the two-way keyboard adapter (58). The switch control (56) controls analog switch (52). Two-way keyboard adapter (58) is connected to both keyboard adapters. The feature bus adapter (60) is connected to the feature bus (44). This allows keystroke signals from the keyboard (12) to be transmitted by the two-way keyboard adapter (58) via the input/output interface (54) and system bus to the memory in the personal computer system unit for interpretation by the microprocessor and then retransmitted back to the two-way keyboard adapter and then to designated one of the keyboard adapters in either the display station or the personal computer system unit. The switch control is responsive to a unique keystroke signal to control the analog input switch (52) so that an operator can control the mode of operation between either a host mode or a personal computer mode. Data transfer can be made between the host computer and the personal computer.