1462:
drives in Japan only supported a capacity of 1.2 MB instead of the 1440 KB capacity that was used elsewhere. While the more common 1440 KB format spun at 300 rpm, the 1.2 MB formats instead spun at 360 rpm, thereby closely resembling the geometries of either the 1.2 MB format with 80 tracks, 15 sectors per track, and 512 bytes per sector previously found on 5.25" high-density floppy disks or the 1.2 MB format with 77 tracks, 8 sectors per track, and 1,024 bytes per sector previously found on 8" double-density floppy disks. Later
Japanese floppy drives incorporated support for both high-density formats (as well as the double-density format), hence the name 3-mode. Some
1450:
40:
94:. Early controllers required additional circuitry to perform specific tasks like providing clock signals and setting various options. Later designs included more of this functionality on the controller and reduced the complexity of the external circuitry; single-chip solutions were common by the later 1980s.
201:, is built with only 8 ICs. It, like the much earlier IBM 3830 FDC, achieved the reduction in components thru use of the host processor and firmware. Its interface to the Apple host as well as its interface to the Apple 5ΒΌ-inch floppy disk drive is unique and it was not adopted as an industry standard.
292:
The controller also provides a number of other services to control the drive mechanism itself. These typically include the movement of the drive head to center over the separate tracks on the disk, tracking the location of the head and returning it to zero, and sometimes functionally to format a disk
269:
as the disk surface rotates past it. It is the timing of these polarization changes and the resulting spikes of voltage that encode the ones and zeros of the original data. One of the functions of the controller is to turn the original data into the proper pattern of polarizations during writing, and
168:
is a type of microcontroller that accepts commands from the system's microprocessor ("MPU" in IBM's terminology) and executes them on the attached 33FD as independently as possible. It accepts and executes the following commands, select/stop, write check, seek lower, seek higher, read data, read I D,
189:
introduced the first 5ΒΌ-inch floppy disk drive along with an associated and first FDC for this form factor, the SA4400. The SA4400 performs control functions to transfer data between a host system and up to 3 disk drives using an 8-bit general purpose host interface which format disks according to a
1461:
Primarily in Japan there are 3.5" high-density floppy drives that support three modes of disk formats instead of the normal two β 1440 KB (2 MB unformatted), 1.2 MB (1.6 MB unformatted) and 720 KB (1 MB unformatted). Originally, the high-density modes for 3.5" floppy
576:
This port is used by the software to read the overall status information regarding the FDC IC and the FDD's. Before initiating a floppy disk operation the software reads this port to confirm the readiness condition of the FDC and the disk drives to verify the status of the previously initiated
773:
A controller connects to one or more drives using a flat ribbon cable, 50 wires for 8" drives and 34 wires for 3.5" & 5.25" drives. A "universal cable" has four drive connectors, two each for 3.5" & 5.25" drives. In the IBM PC family and compatibles, a twist in the cable is used to
190:
modified IBM 3740 type media format specifications. The FDC is microprocesser controlled and implemented on a 5.75 by 9.50 inch pcb with 45 ICs. The drive interface and media form factors became industry standards with the media then evolving over time to support a number of
774:
distinguish disk drives by the socket to which they are connected. All drives are installed with the same drive select address set, and the twist in the cable interchanges the drive select lines at the socket. The drive that is at the far end of the cable would also have a
173:
on the motherboard plus a separate data separator (VFO) pcb. This IBM FDC did establish the IBM Type 1 diskette as the first industry standard floppy disk medium but neither its interface to the host microprocessor nor its interface to the 33FD were adopted as industry
177:
1974: iCOM's FD360 contained an early FDC, the CF 360, that generated industry standard media, connected to industry standard host busses, and supported industry standard FDDs. Its FDC was implemented on a pcb approximately 12x9 inches as a state machine using 30
336:
for a simplified drive that lacked most of its normal circuitry. This meant that the combined cost of a single drive and controller card was roughly the same as on other systems, but a second drive could be connected for a smaller additional cost.
228:(1981); the FDC was physically located on its own adapter card along with support circuitry. Other vendors such as Intel produced compatible parts. This design evolved over time into a family offering an almost complete FDC on a chip.
1767:
A General
Purpose Host Interface is also provided for easy interface to host systems such as minicomputer, microprocessor I/O busses, CRT terminals, instruments, TTL/MSI microprocessors, industrial controllers and other byte oriented
277:. As the on-disk timing is constantly changing, the clock signal has to be provided by the disk itself. To do this, the original data is modified with extra transitions to allow the clock signal to be encoded in the data and then use
331:
The original Apple II controller was in the form of a plug-in card on the host computer. It could support two drives, and the drives eliminated most of the normal onboard circuitry. This allowed Apple to arrange a deal with
1533:
The control unit contains a miniature direct access device which provides read-only storage for control logic backup and storage of nonresident microdiagnostics. The recording medium is an inexpensive Mylar-coated disk
1444:
181:
1976: Scientific Micro
Systems' FD0300 FDC built on an 8-inch by 12-inch circuit board contains a microprocessor and approximately 50 integrated circuits and is designed to provide easy attachment to a number of host
563:
After a command is executed, the FDC IC stores a set of status parameters in the internal registers. These are read by the CPU through this port. The different status bytes are presented by the FDC IC in a specific
145:
hybrid circuits on a few printed circuit cards. The drive, FDC and media were proprietary to IBM and although other manufacturers provided early FDDs prior to 1973 there were no standards for FDCs, drives or media.
2023:
Kearns, Patrick, Begur, Sridhar, and
Fischer, Steve, "High Integration/High Performance Floppy Disk Controller Subsystem with the 82072", Intel Corporation, Microcomputer Solutions, November/December 1987, page
71:(IC or "chip") or a component thereof. An FDC is responsible for reading data presented from the host computer and converting it to the drive's on-disk format using one of a number of encoding schemes, like
560:
While issuing a command to the FDC IC, command and command parameter bytes are issued to the FDC IC through this port. The FDC IC stores the different parameters and the command in its internal registers.
157:
diskette, which coupled with rapidly increasing requirements for inexpensive, removable direct access storage for many small applications caused a dramatic growth in drive and controller shipments.
296:
To produce a complete system, the controller has to be combined with additional circuitry or software that acts as a bridge between the controller and the host system. In some systems, like the
160:
Prior to the introduction of special purpose integrated circuit versions, most FDCs consisted of at least one printed circuit implemented with 40 or more ICs. Examples of such FDCs include:
352:(ISA) bus or similar bus and communicates with the floppy disk drive with a 34 pin ribbon cable. An alternative arrangement that is more usual in recent designs has the FDC included in a
141:. The IBM 3830 Storage Control Unit, a contemporaneous and quite similar controller, uses its internal processor to control a 23FD. The resultant FDC is a simple implementation in IBMs'
273:
As the storage is based on timing, and that timing is easily affected by mechanical and electrical disturbances, accurately reading the data requires some sort of reference signal, the
2244:
2164:
281:
during reads to recreate the original signal. Some controllers require this encoding to be performed externally, but most designs provide standard encodings like
782:
More detailed descriptions of the interface signals including alternative meanings are contained in manufacturer's specifications for drives or host controllers.
790:
and USB floppy disk drives, the internal floppy disk drive and its interface are unchanged, while the assembled device presents a different interface such as
245:
chip. However, in later motherboards, as floppy disks were phased out by personal computer users, this interface was eliminated. Some manufacturers developed
567:
In the programmed and interrupt mode of data transfer, the data port is used for transferring data between the FDC IC and the CPU IN or OUT instruction.
209:
announced on 19 July 1976. The initial design supported a single format and required additional circuitry but over time, as a family, the design became
113:
that could be used with any computer. In more modern systems, the FDC, if present at all, is typically part of the many functions provided by a single
816:
Many mutually incompatible floppy disk formats are possible; aside from the physical format on the disk, incompatible file systems are also possible.
220:
The NEC ΞΌPD765 was announced in 1978 and in 1979 NEC introduced the ΞΌPD72068, which was software compatible with the ΞΌPD765, incorporating a
Digital
2416:
2327:
2014:
Intel
Corporation, "New Product Focus Components: Single-Chip Disk Controller Squeeze More into Less", Solutions, January/February 1987, page 14
393:
488:
The first two reside inside the FDC IC while the
Control port is in the external hardware. The addresses of these three ports are as follows.
2571:
2387:
1990:
1688:
the controller is fully IBM 3740 and 3540 compatible with all formatting and deformatting accomplished automatically within the controller.
2248:
130:
1835:
2566:
2150:
1878:
Pioneering this field was
Western Digital Corporation who, in 1976, began sampling the first LSI floppy disk controller, the FD1771.
234:
In early 1987, Intel introduced the 82072 CHMOS High
Integrated Floppy Disk Controller for use in industry standard PC computers.
1809:
265:
in value. Each of these changes, recorded in the polarity of the magnetic recording media, causes a voltage to be induced in the
364:
786:
When the controller and disk drive are assembled as one device, as it is the case with some external floppy disk drives, e.g.,
1780:
1672:
349:
82:
Depending on the platform, data transfers between the controller and host computer would be controlled by the computer's own
169:
write data, write control, write I D, set ready, reset access counter, and nothing (no-op). It was implemented using IBM's
2492:
2060:
1407:
1396:
389:
385:
286:
1565:
Hardware has already added 64 words (Track 0, Sector 0) and this microprogram will load the remainder of control storage.
2576:
282:
110:
1449:
1497:
1492:
811:
768:
191:
154:
715:
This port is used by the software to control certain FDD and FDC IC functions. The bit assignments of this port are:
39:
2364:
1916:
1517:
2459:
1860:
2270:
1622:
138:
134:
375:
but some are performed by external hardware circuits. The list of functions performed by each is given below.
2405:
411:
340:
The IBM PC took a more conventional approach, their adaptor card could support up to four drives; on the PC
242:
1751:
67:(FDD). It has evolved from a discrete set of components on one or more circuit boards to a special-purpose
2433:
1700:
1480:
1475:
842:
775:
214:
210:
206:
198:
170:
142:
2453:
1594:
1486:
449:
397:
348:
6. The diagram below shows a conventional floppy disk controller which communicates with the CPU via an
317:
301:
225:
44:
2324:
1549:
341:
48:
293:
based on simple inputs like the number of tracks, sectors per track and number of bytes per sector.
1577:
Porter, James N. (August 1977). 1977 DISK/TREND REPORT β FLEXIBLE DISK DRIVES (Report). p. 26.
321:
87:
2391:
1941:
1426:
372:
333:
186:
129:
drive (the IBM 23FD) shipped in 1971 as a component in the IBM 2385 Storage
Control Unit for the
68:
1969:
2146:
1420:
1381:
1375:
417:
345:
320:, there is no direct path from the controller to the host CPU and a second processor like the
31:
2344:
2297:
iesleonardo.info β This diskette tutorial provides technical information concerning diskettes
101:, which required similar controllers. In these systems, the controller also often combined a
63:) is a hardware component that directs and controls reading from and writing to a computer's
2095:
1454:
79:(double density), and reading those formats and returning it to its original binary values.
2468:
2331:
2296:
2186:
2117:
1725:
850:
102:
2546:
2375:
2551:
2525:
1432:
1403:
1392:
1171:
934:
787:
309:
305:
278:
83:
2560:
2211:
1646:
795:
357:
2376:
mcamafia.de β IBM Personal system/2, 3,5"-inch Diskette Drives, Technical Reference
1414:
313:
274:
76:
1518:"IBM 2835 Storage Control and IBM 2305 Fixed Head Storage Module Reference Manual"
1466:
have a configuration setting to enable this mode for floppy drives supporting it.
224:. The ΞΌPD765 became a quasi-industry standard when it was adopted in the original
27:
Circuitry that controls reading from and writing to a computer's floppy disk drive
2505:
2310:
2067:
455:
431:
258:
153:
created the basic media standard for the 8-inch single sided floppy disk, IBM's
126:
72:
64:
2118:"Floppy Drive Pinout, Signal names, Pin out Description and Cable twist wiring"
1890:
266:
98:
642:
DIO; Indicates the direction of data transfer between the FDC IC and the CPU
1142:
443:
Enable/disable interrupt and DMA signals in the floppy disk controller (FDC)
353:
325:
238:
114:
91:
2035:
1610:
At the time, all the existing floppy-disk controllers were 40 or 50 chips β¦
791:
407:
297:
205:
The first FDC implemented as a special purpose integrated circuit is the
165:
150:
1836:"Apple II Computer Family Information, Schematic: Disk 2 Interface Card"
677:
1 = controller has data for CPU, 0 = controller expecting data from CPU
371:
Most of the floppy disk controller (FDC) functions are performed by the
308:
and the drive interface is connected directly to the processor using an
2472:
2311:
oldskool.org β Let HD 5,25" FDDs operate at 300 rpm instead of 360 rpm
403:
Interpret and execute commands such as seek, read, write, format, etc.
17:
1544:
1542:
836:
363:
2501:
1333:
1200:
362:
367:
Block diagram showing FDC communication with the CPU and the FDD.
2547:
viralpatel.net A Tutorial on Programming Floppy Disk Controller
1463:
556:
This port is used by the software for three different purposes:
304:, this is controlled by software running on the computer's host
106:
2461:
NEC ΞΌPD72070 β Floppy Disk Controller Specification Version 2.0
237:
Ultimately in most computer systems the FDC became a part of a
2504:
Corporation, IMD Marketing. AP-358, 292093-002. Archived from
2040:
Scott Muellers Upgrading and Repairing Laptops, Second Edition
1550:"IBM Maintenance Library β Storage Control, Model 2, Volume 2"
799:
577:
command. The different bits of this register represent :
471:
261:
stores binary data not as a series of values, but a series of
246:
221:
1457:
4.3, provided with 3.5" 1.2 MB and 1440 KB formats.
97:
By the 1990s, the floppy disk was increasingly giving way to
125:
The first floppy disk drive controller (FDC) like the first
2271:"Product specification TM100-4 flexible disk drive 96, tpi"
1706:(Report). iCOM Microperipherals. March 1976. pp. 8, 34
685:
1 = Controller Not in DMA Mode, 0 = Controller in DMA Mode
231:
As of March 1986, Sharp had commercialized the FDC LH0110.
1595:"THE APPLE STORY, PART 2, An interview with Steve Wozniak"
1555:. 4 June 1973. pp. MPL 25A, MPL 200, MPL 245, MPL 260
756:
Turn ON the motor in disk drive 0, 1, 2 or 3 respectively
344:(DMA) to the drives was performed using DMA channel 2 and
105:
to handle data transfer over standardized connectors like
217:
to support many formats and minimize external circuitry.
650:
MQR; Indicates data register is ready for data transfer
2365:
yi.org β High Density Floppy Disks Mf2hd Disk 3 5 1 Pk
1942:"NEC Electronics Inc. ΞΌPD72068 Floppy-Disk Controller"
1647:"First floppy disc peripheral made for microcomputers"
86:, or an inexpensive dedicated microprocessor like the
1917:"ΞΌPD765 SINGLE/DOUBLE DENSITY FLOPPY DISK CONTROLLER"
669:
1 = data register ready, 0 = data register not ready
133:
fixed head disk drive, and of the System 370 Models
2406:
books.google.com β Fix Your Own PC by Corey Sandler
1279:
2434:"There is no such thing as a 3.5-inch floppy disc"
2325:intel.com β Intel 82077SL for Super Dense Floppies
2526:"The first floppy controller for CP/M and S-100?"
1859:Joe, Jaworski (1985). "Floppy Disk Controllers".
1810:"SA4400 ministreaker FloppyDisk Drive Controller"
1627:. IBM. 15 May 1974. pp. 14β2.14β15 (488/599)
2552:isdaman.com Programming Floppy Disk Controllers
1963:
1961:
466:Input/output ports for common x86-PC controller
461:Line receivers for signals from the controller
748:Enable FDC interrupt and DMA request signals
8:
2212:"C 64 Workshop / C= 8 Bit & Peripherals"
1066:Up to 83 tracks. Different biasing current.
30:"3-mode" redirects here. For the logic, see
2185:Ableman, Genna (2005). Elert, Glenn (ed.).
2143:Upgrading and Repairing PCs, Second Edition
1868:(Technical report). p. SEMI-1 (67/160)
328:is used inside the drive for this purpose.
2096:"USB Floppy Disk Controller USB97CFDC2-01"
1593:Gregg, Williams; Moore, Rob, eds. (1984).
2292:
2290:
2083:Licensed CMOS 765B Floppy Disk Controller
626:FDC Busy; Read/Write command in progress
440:Reset signal for the floppy controller IC
2450:ISO 10994-1:1992 Extra-high-density (ED)
2343:Johnson, Herbert R. (22 December 2016).
1701:SCHEMATIC AND LOGIC DIAGRAMS MODEL FD360
1448:
818:
717:
655:
579:
490:
38:
2444:ISO/IEC 8860-1:1987 Double-Density (DD)
2320:
2318:
2306:
2304:
2239:
2237:
2235:
2233:
2231:
2229:
1509:
2494:Intel 82077SL for Super-Dense Floppies
987:8/9/10 512 byte sectors respectively.
778:installed to maintain signal quality.
379:Floppy disk controller functions (FDC)
2447:ISO/IEC 9529-1:1989 High-Density (HD)
2388:"Linux-2.6.17/drivers/block/floppy.c"
1624:3741 Data Station, Theory-Maintenance
1588:
1586:
1584:
47:. The NEC D765AC FDC IC is the large
7:
2245:"unifr.ch β sys/src/kernel/floppy.c"
1991:"Sharp 1986 Semiconductor Data Book"
2432:de Boyne Pollard, Jonathan (2003).
2417:rojakpot.com β 3mode floppy support
1862:1985 Controller Concepts β Volume 1
437:Switching-on the floppy drive motor
1781:"State of the Art Disk Technology"
763:Interface to the floppy disk drive
410:generation and verification, like
25:
2500:(Application Note) (2 ed.).
2061:"FDC37C78 Floppy Disk Controller"
1970:"The floppy controller evolution"
197:1977: The Apple Disc II FDC, the
2187:"Angular speed of a floppy disk"
1653:. 27 September 1974. p. 138
400:format to be able to record them
249:-based floppy disk controllers.
2163:Fisher, Tim (18 January 2022).
1968:Necasek, Michal (26 May 2011).
1752:"FD0300 FLOPPY DISK CONTROLLER"
1732:. November 1976. pp. 65β66
1673:"CF 360 FLOPPY DISK CONTROLLER"
270:then recreate it during reads.
149:IBM's 1973 introduction of the
2471:. October 1991. Archived from
2165:"What Is a Floppy Disk Drive?"
356:chip which communicates via a
350:Industry Standard Architecture
1:
2116:Davis, Larry (13 June 2015).
1834:Craig, David T (April 1978).
732:Device number to be selected
701:1 = Running, 0 = Not Running
458:for signals to the controller
312:. On other systems, like the
2572:Floppy disk computer storage
2066:. SMSC. 2007. Archived from
1498:List of floppy disk formats
1493:Floppy disk drive interface
1358:
1355:
1352:
1349:
1346:
1343:
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1329:
1326:
1323:
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1234:
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1207:
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1190:
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1167:
1164:
1161:
1158:
1155:
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1149:
1138:
1135:
1132:
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1127:
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1113:
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1098:
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1088:
1085:
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1079:
1076:
1073:
1070:
1062:
1059:
1056:
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1050:
1047:
1044:
1037:
1034:
1031:
1028:
1025:
1022:
1019:
1012:
1009:
1006:
1003:
1000:
997:
991:
983:
980:
977:
974:
971:
968:
965:
958:
955:
953:
950:
947:
944:
941:
929:
926:
923:
918:
915:
912:
909:
902:
899:
897:
894:
891:
888:
885:
877:
874:
871:
868:
865:
862:
859:
812:List of floppy disk formats
769:Floppy disk drive interface
425:External hardware functions
2593:
1442:
809:
766:
572:Main status register (MSR)
481:Main status register (MSR)
29:
2396:090504 gelato.unsw.edu.au
1891:"Recent IC Announcements"
1453:A setup disk of Japanese
1199:Up to 83 tracks. Used by
961:Only on old controllers.
905:Only on old controllers.
881:Only on old controllers.
618:FDD 3: Busy in seek mode
610:FDD 2: Busy in seek mode
602:FDD 1: Busy in seek mode
594:FDD 0: Busy in seek mode
384:Translate data bits into
2567:Computer storage devices
2491:Shah, Katen A. (1996) .
2438:Frequently Given Answers
2345:"Floppy Drive Tech Info"
2036:"Motherboard Components"
2034:Mueller, Scott (2005).
1678:. iCOM Microperipherals
693:1 = Busy, 0 = Not Busy
2524:Johnson, Herb (2009).
2330:8 October 2012 at the
1481:Integrated Woz Machine
1476:Western Digital FD1771
1458:
450:Write pre-compensation
434:drive (FDD) to address
416:Synchronize data with
368:
207:Western Digital FD1771
151:3740 Data Entry System
57:floppy-disk controller
52:
1452:
767:Further information:
446:Data separation logic
406:Error detection with
366:
318:Atari 8-bit computers
42:
2191:The Physics Factbook
1922:. NEC. December 1978
1445:ja:3γ’γΌγγγγγγΌγγ£γΉγ―γγ©γ€γ
972:320/360/400 KB
776:terminating resistor
711:Digital control port
539:Digital control port
525:Main status register
484:Digital control port
342:direct memory access
75:(single density) or
49:dual in-line package
2577:Integrated circuits
2467:. 2.0 preliminary.
2105:. 13 December 2001.
2073:on 13 December 2007
1439:3-mode floppy drive
998:5.25-inch QD (2DD)
740:RESET FDC IC (Low)
430:Selection of which
171:MST hybrid circuits
2394:on 23 August 2008.
1996:. pp. 279β295
1489:(Amiga controller)
1459:
1427:Extra-high density
517:Bidirectional I/O
474:ports. These are:
470:The FDC has three
373:integrated circuit
369:
334:Shugart Associates
187:Shugart Associates
69:integrated circuit
53:
43:FDC board from an
1651:Electronic Design
1366:
1365:
1362:Up to 83 tracks.
1307:Up to 83 tracks.
1278:Up to 83 tracks.
1252:Up to 83 tracks.
1117:Up to 83 tracks.
1091:Up to 83 tracks.
760:
759:
705:
704:
654:
653:
549:
548:
542:External hardware
418:phase-locked loop
192:different formats
164:1973: The FDC in
65:floppy disk drive
32:Three-state logic
16:(Redirected from
2584:
2536:
2534:
2532:
2520:
2518:
2516:
2510:
2499:
2487:
2485:
2483:
2478:on 20 March 2017
2477:
2466:
2441:
2419:
2414:
2408:
2403:
2397:
2395:
2390:. Archived from
2384:
2378:
2373:
2367:
2362:
2356:
2355:
2353:
2351:
2340:
2334:
2322:
2313:
2308:
2299:
2294:
2285:
2284:
2282:
2280:
2275:
2267:
2261:
2260:
2258:
2256:
2247:. Archived from
2241:
2224:
2223:
2221:
2219:
2208:
2202:
2201:
2199:
2197:
2182:
2176:
2175:
2173:
2171:
2160:
2154:
2139:
2133:
2132:
2130:
2128:
2122:interfacebus.com
2113:
2107:
2106:
2100:
2092:
2086:
2085:
2080:
2078:
2072:
2065:
2057:
2051:
2050:
2048:
2046:
2031:
2025:
2021:
2015:
2012:
2006:
2005:
2003:
2001:
1995:
1987:
1981:
1980:
1978:
1976:
1965:
1956:
1955:
1953:
1951:
1946:
1938:
1932:
1931:
1929:
1927:
1921:
1913:
1907:
1906:
1904:
1902:
1887:
1881:
1880:
1875:
1873:
1867:
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1455:Microsoft Office
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2511:on 19 June 2017
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2469:NEC Corporation
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2426:Further reading
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2251:on 19 July 2011
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1790:. December 1976
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913:5.25-inch SSDD
910:5.25-inch SSDD
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724:Representation
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586:Representation
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103:microcontroller
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2541:External links
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1523:. October 1983
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1443:Main article:
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1433:Triple density
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1404:Double density
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1393:Single density
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310:expansion card
306:microprocessor
279:clock recovery
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84:microprocessor
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2214:. 19 May 1998
2213:
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2151:0-88022-856-3
2148:
2145:, Que, 1992,
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1730:INTERFACE AGE
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1413:QD (or 4D) β
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1402:DD (or 2D) β
1401:
1398:
1394:
1391:SD (or 1D) β
1390:
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1380:DS (or 2S) β
1379:
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1374:SS (or 1S) β
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1043:
1040:
1023:5.25-inch DD
1020:5.25-inch HD
1018:
1015:
992:5.25-inch DD
990:
986:
969:5.25-inch DD
966:5.25-inch DD
964:
960:
945:5.25-inch SD
942:5.25-inch SD
940:
937:compatibles.
936:
932:
908:
904:
889:5.25-inch SD
886:5.25-inch SD
884:
880:
858:
854:
852:
849:
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844:
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838:
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827:
824:
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797:
796:parallel port
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634:Non-DMA mode
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358:Low Pin Count
355:
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211:multi-sourced
208:
200:
199:"Woz Machine"
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80:
78:
74:
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66:
62:
58:
50:
46:
41:
37:
33:
19:
2529:. Retrieved
2513:. Retrieved
2506:the original
2493:
2480:. Retrieved
2473:the original
2460:
2437:
2412:
2401:
2392:the original
2382:
2371:
2360:
2348:. Retrieved
2338:
2277:. Retrieved
2265:
2253:. Retrieved
2249:the original
2216:. Retrieved
2206:
2194:. Retrieved
2190:
2180:
2170:20 September
2168:. Retrieved
2158:
2142:
2137:
2125:. Retrieved
2121:
2111:
2102:
2090:
2082:
2075:. Retrieved
2068:the original
2055:
2043:. Retrieved
2039:
2029:
2019:
2010:
1998:. Retrieved
1985:
1973:. Retrieved
1948:. Retrieved
1936:
1924:. Retrieved
1911:
1899:. Retrieved
1897:. IEEE. 1976
1894:
1885:
1877:
1870:. Retrieved
1861:
1854:
1842:. Retrieved
1829:
1817:. Retrieved
1804:
1792:. Retrieved
1787:
1775:
1766:
1759:. Retrieved
1746:
1734:. Retrieved
1729:
1720:
1708:. Retrieved
1695:
1687:
1680:. Retrieved
1667:
1655:. Retrieved
1650:
1641:
1629:. Retrieved
1623:
1617:
1609:
1602:. Retrieved
1598:
1572:
1564:
1557:. Retrieved
1532:
1525:. Retrieved
1512:
1460:
1421:High density
1415:Quad density
1406:(most often
1386:
1382:Double sided
1376:Single sided
1369:
1367:
1026:360 KB
1001:800 KB
948:180 KB
916:171 KB
892:160 KB
815:
785:
772:
714:
706:
659:Explanations
575:
555:
494:Port Address
487:
469:
456:Line drivers
370:
360:(LPC) bus.
339:
330:
314:Commodore 64
295:
291:
272:
262:
256:
236:
233:
230:
219:
204:
159:
148:
124:
96:
81:
77:MFM encoding
60:
56:
54:
36:
2531:9 September
2077:9 September
2045:5 September
1975:2 September
1926:9 September
1872:9 September
1819:1 September
1794:1 September
1336:computers.
1203:computers.
866:80 KB
806:Format data
698:FDD 0,1,2,3
432:floppy disk
259:floppy disk
243:Southbridge
127:floppy disk
99:hard drives
73:FM encoding
51:at the top.
2561:Categories
2350:14 January
2196:25 January
2153:, page 487
2127:29 January
2000:14 January
1950:24 January
1534:cartridge.
1504:References
863:8-inch SD
860:8-inch SD
504:Port type
267:drive head
241:chip or a
174:standards.
166:IBM's 3741
2279:8 January
1710:11 August
1682:19 August
1657:11 August
1387:Density:
1143:Macintosh
1074:5.25" HD
1071:5.25" HD
1048:5.25" HD
1045:5.25" HD
564:sequence.
552:Data port
512:Data port
498:Port Name
478:Data port
408:checksums
354:super I/O
326:Zilog Z80
239:Super I/O
115:super I/O
92:Zilog Z80
2482:20 March
2454:ECMA-147
2328:Archived
2218:18 April
2103:keil.com
1901:6 August
1895:Computer
1844:6 August
1768:systems.
1631:9 August
1604:6 August
1470:See also
1347:2880 KB
1344:3.5" ED
1341:3.5" ED
1332:Used by
1318:1760 KB
1315:3.5" HD
1312:3.5" HD
1292:1440 KB
1289:3.5" HD
1286:3.5" HD
1263:1280 KB
1260:3.5" HD
1257:3.5" HD
1235:3.5" DD
1232:3.5" HD
1211:3.5" DD
1208:3.5" DD
1182:3.5" DD
1179:3.5" DD
1170:Used by
1153:3.5" DD
1150:3.5" DD
1133:394β590
1125:3.5" DD
1122:3.5" DD
1099:3.5" DD
1096:3.5" DD
1051:1200 KB
994:(96 tpi)
933:Only on
855:Comment
831:Transfer
828:Capacity
792:IEEE-488
690:FDC Busy
501:Location
322:MOS 6507
298:Apple II
253:Overview
155:"Type 1"
131:IBM 2305
88:MOS 6507
45:IBM 5150
2515:19 June
1761:24 July
1736:24 July
1726:"Discs"
1559:29 July
1527:22 July
1370:Sides:
1280:"3mode"
1238:720 KB
1214:360 KB
1185:880 KB
1156:800 KB
1128:800 KB
1102:720 KB
1077:720 KB
920:250β308
869:33.333
729:0 and 1
707:
682:Non-DMA
545:Output
263:changes
215:evolved
121:History
2149:
1815:. 1977
1757:. 1976
1464:BIOSes
847:Tracks
837:kbit/s
825:Format
753:4 to 7
531:Input
528:FDC IC
302:IBM PC
226:IBM PC
185:1976:
182:buses.
117:chip.
18:3-mode
2509:(PDF)
2502:Intel
2498:(PDF)
2476:(PDF)
2465:(PDF)
2274:(PDF)
2255:5 May
2099:(PDF)
2071:(PDF)
2064:(PDF)
1994:(PDF)
1945:(PDF)
1920:(PDF)
1866:(PDF)
1839:(PDF)
1813:(PDF)
1784:(PDF)
1755:(PDF)
1704:(PDF)
1676:(PDF)
1553:(PDF)
1521:(PDF)
1487:Paula
1483:(IWM)
1431:TD β
1425:ED β
1419:HD β
1350:1000
1334:Amiga
1201:Amiga
935:C1541
839:]
835:[
833:speed
822:Drive
452:logic
420:(PLL)
396:, or
275:clock
2533:2022
2517:2017
2484:2017
2352:2017
2281:2022
2257:2011
2220:2016
2198:2022
2172:2022
2147:ISBN
2129:2019
2079:2022
2047:2022
2002:2024
1977:2022
1952:2024
1928:2022
1903:2022
1874:2022
1846:2022
1821:2022
1796:2022
1788:Byte
1763:2022
1738:2022
1712:2022
1684:2022
1659:2022
1633:2022
1606:2022
1599:Byte
1561:2022
1529:2022
1359:135
1353:300
1324:150
1321:250
1304:135
1298:300
1295:500
1275:135
1269:360
1266:500
1244:300
1241:250
1220:300
1217:250
1191:300
1188:250
1162:300
1159:250
1114:135
1108:300
1105:250
1083:360
1080:300
1057:360
1054:500
1032:360
1029:300
1007:300
1004:250
978:300
975:250
951:150
924:300
895:125
872:360
394:MΒ²FM
316:and
300:and
285:and
213:and
178:ICs.
137:and
109:and
107:SCSI
1408:MFM
1356:80
1327:80
1301:80
1272:80
1247:80
1223:40
1194:80
1165:80
1136:80
1111:80
1086:80
1063:96
1060:80
1038:48
1035:40
1013:96
1010:80
984:48
981:40
956:40
930:48
927:35
900:40
878:48
875:32
851:TPI
843:RPM
800:USB
798:or
721:Bit
674:DIO
666:MQR
583:Bit
536:3F2
522:3F4
509:3F5
472:I/O
412:CRC
398:GCR
390:MFM
346:IRQ
324:or
287:MFM
247:USB
222:PLL
143:MST
139:165
135:155
111:IDE
90:or
61:FDC
2563::
2436:.
2317:^
2303:^
2289:^
2228:^
2189:.
2120:.
2101:.
2081:.
2038:.
2024:20
1960:^
1893:.
1876:.
1786:.
1765:.
1728:.
1686:.
1649:.
1608:.
1597:.
1583:^
1563:.
1541:^
1531:.
1397:FM
1174:.
1145:.
802:.
794:,
392:,
388:,
386:FM
289:.
283:FM
257:A
55:A
2535:.
2519:.
2486:.
2440:.
2354:.
2283:.
2259:.
2222:.
2200:.
2174:.
2131:.
2049:.
2004:.
1979:.
1954:.
1930:.
1905:.
1848:.
1823:.
1798:.
1740:.
1714:.
1661:.
1635:.
1410:)
1399:)
1395:(
745:3
737:2
647:7
639:6
631:5
623:4
615:3
607:2
599:1
591:0
194:.
59:(
34:.
20:)
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