| 摘要 |
PURPOSE:To ensure transfer of data with high system efficiency by always monitoring the using frequency of a system bus every unit time and switching a data transfer mode using the system bus to a burst mode or a normal mode in accordance with the using frequency of the bus. CONSTITUTION:A bus using frequency measuring part 31 of an equipment 30-1 measures the bus using frequency for each unit time T via a signal line 34 and based on a bus request signal supplied through a bus request signal line of a system bus 20. A control part 32 of the equipment 30-1 informs a start request to a bus interface part 33 when the transfer of data is needed with another equipment via the bus 20. The part 33 decides that the transfer of data is permitted in a burst mode when a bus using frequency display signal is equal to logic '0' and therefore the latest using frequency of the bus 20 is less than a reference level. While the part 33 decides that the transfer of data is not permitted in a burst mode when the bus using frequency display signal is equal to logic '1' and therefore the latest using frequency of the bus 20 is more than the reference level. |
