Document
IIVESTERIV DIGITAL
CDR PO RAT /0 N
FD1791A/B Floppy Disk Formatter/Controller
FEATURES
• SOFT SECTOR FORMAT COMPATIBILITY • AUTOMATIC TRACK SEEK WITH VERIFI-
CATION • ACCOMMODATES SINGLE AND DOUBLE
DENSITY FORMATS IBM 3740 Single Density (FM) IBM System 34 Double Density (MFM)
• READ MODE Single/Multiple Record Read with Automatic Search or Entire Track Read Selectable 128 Byte or Variable Length Record
• WRITE MODE Single/Multiple Record Write with Automatic Sector Search Entire Track Write for Diskette Initialization
• PROGRAMMABLE CONTROLS Selectable Track to Track Stepping Time Selectable Head Settling and Head Engage Times
• SYSTEM COMPATIBILITY Double Buffering of Data 8 Bit Bi-Directional Bus for Data, Control and Status D~A or Programmed Data Transfers All Inputs and Outputs are TTL Compatible On-chip Track and Sector Registers Comprehensive Status Information
• WRITE PRECOMPENSATION (MFM AND FM) • WINDOW EXTENSION (IN MFM) • INCORPORATES ENCODING/DECODING
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