Circuit arrangement for inhibiting writing on a magnetic disk during the

Abstract

An electric control system for an apparatus for writing and reading data on and from a flexible magnetic disk under the control of host equipment such as a central processor unit having an associated controller. The control system includes a time setting circuit responsive to stepping pulses, by which the magnetic head is transported from track to track on the disk, for determining an access time to be elapsed from the moment the head starts to be transported from any track on the disk to any other track thereon to the moment the head becomes stably positioned on the new track. Connected to the time setting circuit is an index pulse suppressor circuit which suppresses any index pulse, indicative of the rotation and angular position of the magnetic disk, that is generated during each access time and which permits the delivery to the host equipment of the subsequent index pulses that are generated after the lapse of the access time. A read data suppressor circuit is also provided which inhibits the delivery to the host equipment of any data read from the disk either during the access time or from the moment the transducer head starts moving toward a new track to the moment the first index pulse is generated after the lapse of the access time. Thus the host equipment is conditioned to commence the writing of data only after the head is stably positioned on each new track.