United States Patent [19] [li] Patent Number: 4,947,367
Chang et al. [45] Date of Patent: Aug. 7,1990
[54] SYSTEM FOR CONVERTING DIGITAL
DATA FROM MAGNETIC TAPE FORMAT
APPARATUS AND METHOD FOR
CONVERTING A SEQUENTIALLY
ACCESSIBLE MAGNETIC TAPE DATA
FORMAT TO DIRECTLY ACCESSIBLE
WRITE-ONCE DISK DATA FORMAT TO
WORM OPTICAL DISK FORMAT
[75] Inventors: Christopher Y. Chang, Medfield; Leo C. Sherwin, Marlboro, both of Mass.
[73] Assignee: EMC Corporation, Hopkington, Mass.
[21] Appl. No.: 173,981
[22] Filed: Mar. 28,1988
[51] Int CI.' G06F 7/22; G06F 7/24;
G06F 3/06; G06E 1/02
[52] U.S. CI 364/900; 364/927.81;
364/939.2; 364/952.1; 364/952.31; 364/952.6;
364/960; 364/963.5
[58] Field of Search 360/40, 39, 48, 72.2,
360/15, 32; 364/200 MS File, 900 MS File
[56] References Cited
U.S. PATENT DOCUMENTS
3,573,744 4/1971 Rigazio 364/200
4,000,510 12/1976 Cheney et al 360/33
4,084,231 4/1978 Cappozzi et al 364/200
4,089,028 5/1978 Wells 360/79
4,229,808 10/1980 Hui 365/234
4,238,843 12/1980 Carasso et al 365/234
4,321,635 3/1982 Tsuyuguchi 360/72.2
4,321,670 3/1982 Timmons 364/300
4,355,338 10/1982 Yamamoto et al 360/15
4,467,421 8/1984 White 364/200
4,511,963 4/1985 Kantner 364/200
4,541,019 9/1985 Precourt 360/15
4,575,827 3/1986 Kulakowski 365/230
4,578,722 3/1986 Lovgren et al 360/60
4,701,846 10/1972 Zenzelfllis 178/6.6
OTHER PUBLICATIONS
"IBM DOS Version 3.10 Reference Manual", 2/85, pp.
7-19 to 7-23 and 7-157 to 7-160.
Haim Brill, "Optical Storage System Emulates Format-
ted Tape Drive", Hard Copy, Apr '87, pp. 104-106, 108.
"Optimem 1000 OEM Manual", revision 4, Apr. 1985.
Primary Examiner—Archie E. Williams, Jr.
Assistant Examiner—Ayni Mohamed
Attorney, Agent, or Firm—Weingarten, Schurgin,
Gagnebin & Hayes
[57] ABSTRACT
Apparatus and method for storing magnetic tape format data separately stores the tape data from the taperelated information, such as file markers and interblock gap signals. The data and data-related signals are stored in separate finite length buffer memories, which when filled to a predetermined capacity are transferred to a write-once read-many (WORM) optical disk, and stored in contiguous locations beginning at one end of the addressable space on the optical disk. A separately generated tape record map list, including the WORM optical disk address of the aforementioned tape data and tape-related signals is created and stored on the optical disk in sequentially contiguous locations corresponding to sequential tape reel numbers beginning at the opposite end of the addressable space on the optical disk. The data thus recorded on the WORM optical disk is recoverable in the original magnetic tape format by recomposing the data stored in the WORM optical disk in the original magnetic tape data format. Furthermore, the conversion of data according to the present invention can be adapted to a variety of other formats to be stored to and recovered from the WORM optical disk format.
