Abstract: A method or system to change a display output by a program without modifying the program. The invention also provides a program or computer to accomplish this change in display output. The invention intercepts and converts a graphics display command into the desired configuration and also performs reverse conversion of input data in compliance with computer environment assumed from the program. Additionally the invention converts data exchanged between the program and computer system mutually as needed.

Abstract: A network interface apparatus connected between a LAN adaptor possessed by a computer and a transceiver provided on a network includes a buffer memory for storing data, a first control circuit for communicating with the LAN adaptor, a second control circuit for communicating with the transceiver, and a processor for controlling the first and second control circuits to control the transfer of data between the LAN adaptor and the transceiver. The processor causes the buffer memory to store transmit data transmitted from the LAN adaptor and transmits the stored transmit data in the buffer memory to the transceiver in a transmission time zone which is allotted beforehand. The transmission time zone is determined by the processor on the basis of the reception of a synchronizing packet which is transferred on the network. Receive data received from the transceiver is selected by the processor so that only the selected receive data is sent to the LAN adaptor.

Abstract: A distributed memory computer system periodically performs memory copy among a plurality of computers by using general-purpose communication control devices and a transmission line of the CSMA/CD type. A master computer periodically generates a synchronizing packet, and transmits data for memory copy and normal data in a time slot immediately after the transmission of the synchronizing packet. Each computer other than the master computer transmits the data for memory copy and the normal data in its own time slot after the elapse of a predetermined time. The respective computers complete their transmissions within predetermined times. Since the time slots are assigned to the respective computers, the number of computers which may compete with each other on a transmission line can be restricted and each computer can be assured a periodic opportunity to transmit data.