Datasheet Details
| Part number | FD1771 |
|---|---|
| Manufacturer | Western Digital |
| File Size | 1.05 MB |
| Description | FLOPPY DISK FORMATTER/CONTROLlER |
| Datasheet | FD1771-WesternDigital.pdf |
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Overview: WESTERN DIGITAl MOS/LSI FD1771 APPLICATION NOTE FLOPPY DISK CONTROLLER APPLICATION NOTE Introduction The FD 1771 is a MOS/LSI device that performs the function of interfacing a processor to a' flexible (Floppy) diskette drive. This single chip replaces nearly 80% of the required disk drive interface electronics. (See figure 1-1) .It provides tha data accessing controls and the bidirectional transfer of information between the processor's memory and the magnetically stored data on the diskette. The diskette data is stored in a data entry format patible with the IBM 3740 specification (other formats may be used providing more data storage). In this format all information is recorded on tracks (radial paths) in sectors (arc sections) defined by a program.: rned heade'r asshown below: FLOPPY DISK FORMATTER/CONTROLlER Index Address Mark Data 1 1 1.1 1 1 0 0 oClock 1 1 0 1 1 1 1 ID Address Mark Data 1 1 1 1 1 1 '1 0 Clock 1 1 00 0 1 1 1 Data Address Mark Data 1 1 1 1 1 0 1 1 Clock 1 1 0 00 1 1 1 Deleted Data 1 1 1 1 1 00 0 Data Address Mark oClock 1 1 0 0 1 1 1 =FC =07 =FE =C7 =FB ==C7 =F8 =C7 These patterns are used as synchronization codes by the FD 1771 when reading data and are recorded by the formatting mand, Write Track, when the FD 1771. is presented with data F7 through FE. Bytt' 1 6 "7 1-128 ,ITrack Byte> Sector ~ector Cyclic gap 2 Datd Data Data .gap 3 Nurntwr of Number U'flytn Hedundancy (17 Adcll"';S' CRe .
| Part number | FD1771 |
|---|---|
| Manufacturer | Western Digital |
| File Size | 1.05 MB |
| Description | FLOPPY DISK FORMATTER/CONTROLlER |
| Datasheet | FD1771-WesternDigital.pdf |
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1.1 FD1771 - Flexible Drive Interface (Refer to Figure 1-1 FD1771 Block Diagram) The FD1771 hand les si ngle density frequency modulated The F01771 generates all controls to position the read/ (FM) data.
Each data cell is defined by clock pulses.
A pulse write head over the desired track.
| Part Number | Description |
|---|---|
| FD1771-01 | FLOPPY DISK FORMATTER/CONTROLlER |
| FD1791-02 | FLOPPY DISK FORMATTER/CONTROLlER |
| FD1791A | Floppy Disk Formatter/Controller |
| FD1791B | Floppy Disk Formatter/Controller |
| FD1793-02 | FLOPPY DISK FORMATTER/CONTROLlER |
| FD1795-02 | FLOPPY DISK FORMATTER/CONTROLlER |
| FD1797-02 | FLOPPY DISK FORMATTER/CONTROLlER |