JPS5679342A - Data processing device - Google Patents

Abstract

PURPOSE: To make it possible to use one memory in common, by accessing the memory for storing the microinstructions by means of time division by plural microprogram control devices, and holding the read-out data until the next access.

CONSTITUTION: The access timing to the memory 6 by the microprogram control device 2 and 2' is executed through shifting the phase by 180° by the clock generation device 3. Accordingly, both the devices 2 and 2' do not cause the waiting status. In this case, the read-out data corresponding to the access timing signals (b) and (c) of the devices 2 and 2' are provided to the output bus 7. At this time, the read-out data holding parts 8 and 8' of the devices 2 and 2' sample the read-out data provided to the bus 7 by the prescribed timing, and hold them until the next timing. Accordingly, the read-out data are held in the holding parts 8 and 8' until the read-out data by the next access timing are provided. Therefore, both the devices 2 and 2' are able to use one memory 6 in common, respectively, in an almost exclusive state.

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