Abstract: A system and method are provided for driving a digital display adapted to depict a first number of bits per color field during each frame. In use, a second number of bits is displayed which is greater than the first number of bits. This is accomplished by alternating the display of the bits between frames. To this end, additional bits of color are displayed without increasing the number of bits per color field during each frame.

Abstract: A system and method are provided for driving a digital display adapted to depict a first number of bits per color field during each frame. In use, a second number of bits is displayed which is greater than the first number of bits. This is accomplished by alternating the display of the bits between frames. To this end, additional bits of color are displayed without increasing the number of bits per color field during each frame.

Abstract: A port emulator circuit implemented on an Apple II peripheral card which enables MS-DOS programs designed to run on an 8086 microprocessor based IBM type personal computer to perform input/output operations on peripheral devices used by 6502 microprocessor based Apple II computers. As the 8086 requires I/O, a state machine, which forms part of the port emulator, performs the required bus arbitration between the 8086 and the 6502 and informs the 6502 of pending requirements of the 8086. The 6502 determines the type of I/O required, and using Apple II hardware resource, performs the I/O operation. The 6502 also places status information concerning the I/O operation in a portion of RAM on the peripheral card, which RAM location emulate the I/O registers found on IBM personal computers.