PURPOSE: To shorten data transfer time by connecting memories to buses on a CPU-side or buses on a LAN controller-side through selectors in correspondence with utilization conditions in a data processor relating to LAN.
CONSTITUTION: A data transmission-side consists of CPU 1 connected to the bus 5, a LAN controller 2 connected to the bus 6, the selector 3 switching the buses 5 and 6 and the memory 4 connected to the bus 5 or the bus 6 through the selector 3. When CPU 1 accesses the memory 4, the selector 3 is switched to the bus 5-side, thereby access is available. When the LAN controller 2 accesses the memory 4, the selector 3 is switched to a bus 6-side. Namely, the memories 4 and 11 are connected to two buses 6 and 13 through the selectors 3 and 10 and the data on the memory 4 can directly be transferred to the reception-side memory 11.
IKEJIMA KIMIO
URUMA KATSUYA
NEC NIIGATA LTD