G - Physics – 11 – B
Patent
G - Physics
11
B
354/235, 352/19.
G11B 5/008 (2006.01) G11B 27/10 (2006.01)
Patent
CA 1092705
A SYSTEM AND METHOD FOR ATTACHING MAGNETIC STORAGE DEVICES HAVING DISSIMILAR TRACK CAPACITIES AND TRACK FORMATS Abstract of the Disclosure A system and method are disclosed for attaching a second magnetic storage device to a storage subsystem which includes one or more first magnetic storage devices. The track capacity of the first device, i.e., the maximum num- ber of bytes per track, is different from the track capa- city of the second device. The information stored on the first device is formatted with a first track format where- in the start of each individual record measured in the number of bytes from the start of the track varies with either the number of records preceding it, or the length of each preceding record, e.g., a count-key-and-data for- mat. The method involves the steps of generating a "bytes used" number is the second device which reflects, at pre- determined times, the number of bytes between the start of a track and the start of each record if the record had been written on the first device in the first format; record- ing the "bytes used" number in a "bytes used" field of each record each time each record is recorded on the sec- ond device; and generating a virtual index signal when the "bytes used" number corresponds to the track capacity of the first device. The system comprises a counter in the second device, a clock signal for stepping the counter at a rate which corresponds to the data rate of the second device, and a plurality of circuits for controlling the operation of the counter so that the contents thereof, at the time each record is to be written, reflects the number of bytes between the start of the track and the start of each record if the record had been written on the first Abstract - Continued device in the first format. Circuit means are also pro- vided for transferring the contents of the counter to the recording circuits of the device at preselected times. The system also includes a signal generator, which is connected to the counter, and, at a time when the contents of the counter corresponds to the track capacity of the first device, issues a virtual index signal.
255550
Bowers Earl Q.
Nelson David L.
International Business Machines Corporation
Na
LandOfFree
System and method for attaching magnetic storage devices... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with System and method for attaching magnetic storage devices..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and System and method for attaching magnetic storage devices... will most certainly appreciate the feedback.
Profile ID: LFCA-PAI-O-814807