Abstract: A personal computer attachment is provided for a display station of the type that communicates with a host computer (48). The display station has a display unit (10) and a keyboard (12) to which a personal computer system unit (14) is attached. The personal computer system unit typically supports floppy diskette drives (16) and a printer (18). The display unit includes a CRT (38), a regeneration buffer (42), a keyboard adapter (46) and a feature bus (44). The personal computer system unit includes a system bus, a microprocessor, memory, a keyboard adapter and I/O interface connected to the system bus. 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). This switch has a second input from the display adapter (26 or 28) and is controlled from inputs from the keyboard (12) to selectively supply image data from the buffer (42 ) or the display adapter (26 or 28).