Misplaced Pages

#565434

129-421: The Rainbow came in three models, the 100A, 100B and 100+. The "A" model was the first released, followed later by the "B" model. The most noticeable differences between the two models were the firmware and slight hardware changes. The systems were referred to with model numbers PC-100A and PC-100B respectively; later "B" models were also designated PC-100B2 . The system included a user-changeable ROM chip in

258-470: A TTL 15 kHz composite-video signal compatible with RS-170 (NTSC) in monochrome mode. With the inclusion of the graphics option, the Rainbow could also output sync-on-green RGB video signals at TTL levels. The Rainbow was most often coupled with the 12-inch VR201 monochrome monitor or the 13-inch VR241 color monitor, both produced by Digital Equipment Corporation . The Rainbow was unique, in that

387-408: A 3330, with optionally three more 3330's bolted together. This is known as a string, making a maximum of eight drives in a string. In August 1972 IBM announced the 3830 Model 2 Storage Control and the 3333 Disk Storage and Control , separating the control unit from the string. The 3830 became a director type of storage control , controlling one or more strings. The now first unit of the string,

516-408: A 3330, with optionally three more 3330's bolted together. This is known as a string, making a maximum of eight drives in a string. In August 1972 IBM announced the 3830 Model 2 Storage Control and the 3333 Disk Storage and Control , separating the control unit from the string. The 3830 became a director type of storage control , controlling one or more strings. The now first unit of the string,

645-424: A Field Engineer while the other drives are in use by the customer. Each drive's system address is determined in part by a user-swappable plug, one such plug denoting a spare drive not system accessible. This permits physically changing the address of a drive by changing the plug. A 2844 Control Unit can be added to the 2314 Control Unit which allows two S/360 Channels simultaneous access to two separate disk drives in

774-424: A Field Engineer while the other drives are in use by the customer. Each drive's system address is determined in part by a user-swappable plug, one such plug denoting a spare drive not system accessible. This permits physically changing the address of a drive by changing the plug. A 2844 Control Unit can be added to the 2314 Control Unit which allows two S/360 Channels simultaneous access to two separate disk drives in

903-432: A big comb. This eliminates the time needed for the arm to pull the head out of one disk and move up or down to a new disk. Seeking the desired track is also faster since, with the new design, the head will usually be somewhere in the middle of the disk, not starting on the outer edge. Maximum access time is reduced to 180 milliseconds. The 1301 is the first disk drive to use heads that are aerodynamically designed to fly over

1032-432: A big comb. This eliminates the time needed for the arm to pull the head out of one disk and move up or down to a new disk. Seeking the desired track is also faster since, with the new design, the head will usually be somewhere in the middle of the disk, not starting on the outer edge. Maximum access time is reduced to 180 milliseconds. The 1301 is the first disk drive to use heads that are aerodynamically designed to fly over

1161-565: A capacity of 5.4 MB and runs at 3.0 MB/second when attached using the 2-byte channel interface. Average access time is 2.5 ms. The larger 2305-2 has a capacity of 11.2 MB and runs at 1.5 MB/second with an average access time of 5 ms. The 2305 provides large-scale IBM computers with fast, continuous access to small-sized quantities of information. Its capacity and high data rate make it ideal for some systems residence functions, work files, job queues, indices and data sets that are used repeatedly. Its fast response time makes it attractive as

1290-565: A capacity of 5.4 MB and runs at 3.0 MB/second when attached using the 2-byte channel interface. Average access time is 2.5 ms. The larger 2305-2 has a capacity of 11.2 MB and runs at 1.5 MB/second with an average access time of 5 ms. The 2305 provides large-scale IBM computers with fast, continuous access to small-sized quantities of information. Its capacity and high data rate make it ideal for some systems residence functions, work files, job queues, indices and data sets that are used repeatedly. Its fast response time makes it attractive as

1419-423: A controller, the models B2 (two drives) and B1 (one drive). B-units can connect to the model A2 to a maximum of eight drives. Winchester disk IBM manufactured magnetic disk storage devices from 1956 to 2003, when it sold its hard disk drive business to Hitachi . Both the hard disk drive (HDD) and floppy disk drive (FDD) were invented by IBM and as such IBM's employees were responsible for many of

SECTION 10

#1732780162566

1548-531: A full track to and from the magnetic core memory of the 653 , an IBM 650 option that included just sixty signed 10-digit words, enough for a single track of disk or a tape record, along with two unrelated features. The IBM 1405 Disk Storage Unit was announced in 1961 and was designed for use with the IBM 1400 series, medium scale business computers. The 1405 Model 1 has a storage capacity of 10 million alphanumeric characters (60,000,000 bits) on 25 disks. Model 2 has

1677-483: A full track to and from the magnetic core memory of the 653 , an IBM 650 option that included just sixty signed 10-digit words, enough for a single track of disk or a tape record, along with two unrelated features. The IBM 1405 Disk Storage Unit was announced in 1961 and was designed for use with the IBM 1400 series, medium scale business computers. The 1405 Model 1 has a storage capacity of 10 million alphanumeric characters (60,000,000 bits) on 25 disks. Model 2 has

1806-730: A good job at emulating the IBM BIOS, its inability to trap references to the video and other hardware limited what would run on the Rainbow. The FOSSIL TSR allowed several terminal programs and editors to run on the IBM-PC, Rainbow, and other early 8088/8086 computers, but its limited adoption hampered its usefulness. Various other hacks allowed popular programs such as Turbo Pascal and Turbo C to run. Such patches circulated, but new releases made these difficult to keep up with, and over time these hacks dried up (the online archives have very little new after 1991 or 1992, although some of that may be due to

1935-454: A layer of compressed air as in the older head design of the IBM 350 disk storage (RAMAC). Production 353s used self-flying heads essentially the same as those of the 1301. The IBM 355 was announced on September 14, 1956, as an addition to the popular IBM 650 . It used the mechanism of the IBM 350 with up to three access arms and stored 6 million decimal digits and 600,000 signs. It transferred

2064-405: A layer of compressed air as in the older head design of the IBM 350 disk storage (RAMAC). Production 353s used self-flying heads essentially the same as those of the 1301. The IBM 355 was announced on September 14, 1956, as an addition to the popular IBM 650 . It used the mechanism of the IBM 350 with up to three access arms and stored 6 million decimal digits and 600,000 signs. It transferred

2193-535: A listing of Microsoft assembly code to handle this. The theory was that hardware interrupts would interrupt again but software interrupts would only happen once. The Rainbow 100B fixed this overlap in hardware by changes to the board design that allowed the OS to move the hardware interrupts. This means that the MS-DOS 3.10b version for the Rainbow can only run on the Rainbow 100B. DEC itself ported Microsoft Windows 1.0 to

2322-423: A maximum access time for model 2 of 800ms and 700ms for model 1. The 1405 model 2 disk storage unit has 100,000 sectors containing either 200 characters in move mode or 178 characters in load mode , which adds a word mark bit to each character. The Model 1 contains 50,000 sectors. The IBM 7300 Disk Storage Unit was designed for use with the IBM 7070 ; IBM announced a model 2 in 1959, but when IBM announced

2451-423: A maximum access time for model 2 of 800ms and 700ms for model 1. The 1405 model 2 disk storage unit has 100,000 sectors containing either 200 characters in move mode or 178 characters in load mode , which adds a word mark bit to each character. The Model 1 contains 50,000 sectors. The IBM 7300 Disk Storage Unit was designed for use with the IBM 7070 ; IBM announced a model 2 in 1959, but when IBM announced

2580-473: A maximum configuration of 892 KB. The "100+" model was actually a marketing designation signifying that the system shipped with a hard drive installed; the "100+" and "B" models were identical in all other respects. When a hard-disk option was installed on the Rainbow, the kit included the 100+ emblem for the computer's case. The Rainbow contained two separate data buses controlled by the Zilog Z80 and

2709-495: A new BBS platform that ran on DOS, they learned of FidoBBS and arranged to have its developer port the serial drivers to the Rainbow platform. This ran up considerable phone bills sending emails and file transfers between St. Louis and the developer in San Francisco , and the developer produced FidoNet as a method of automating exchanges late at night when phone rates were lower. Piers Anthony wrote many of his books from

SECTION 20

#1732780162566

2838-434: A number of expansion slots that could be used for a single purpose only: extra memory, graphics, rx-50 floppy controller. One slot was originally designed for a DMA enabled serial card, but hard disk controllers were used there instead because DEC bet wrong on which was more important. Univation produced an Ethernet card that could boot the Rainbow over the network for that slot. It stacked to allow both hard disk and Ethernet in

2967-602: A number of sources including The Rainbow runs the CP/M-86/80 operating system, which detects whether software is written for 16-bit CP/M-86 or 8-bit CP/M-80 and runs it on the appropriate processor. DEC later released a compatible version of MS-DOS, but little DOS software was released on Rainbow media. While it provided the same MS-DOS functions as IBM's PC DOS , it lacked the IBM PC's video and keyboard ROM BIOS interface which most MS-DOS software relied upon, limiting

3096-552: A paging device in a heavily loaded systems, where there are 1.5 or more transactions per second. The IBM 2311 Disk Storage Drive was introduced with the 2841 Control Unit in 1964 for use throughout the IBM System/360 ; the combination was also available on the IBM 1130 and the IBM 1800 . The drive also directly attaches to the IBM System/360 Model 20 and the IBM System/360 Model 25 . All drives used

3225-417: A paging device in a heavily loaded systems, where there are 1.5 or more transactions per second. The IBM 2311 Disk Storage Drive was introduced with the 2841 Control Unit in 1964 for use throughout the IBM System/360 ; the combination was also available on the IBM 1130 and the IBM 1800 . The drive also directly attaches to the IBM System/360 Model 20 and the IBM System/360 Model 25 . All drives used

3354-451: A pair of heads up and down to select a disk pair (one down surface and one up surface) and in and out to select a recording track of a surface pair. Several improved models were added in the 1950s. The IBM RAMAC 305 system with 350 disk storage leased for $ 3,200 per month. The 350 was officially withdrawn in 1969. U.S. patent 3,503,060 from the RAMAC program is generally considered to be

3483-399: A pair of heads up and down to select a disk pair (one down surface and one up surface) and in and out to select a recording track of a surface pair. Several improved models were added in the 1950s. The IBM RAMAC 305 system with 350 disk storage leased for $ 3,200 per month. The 350 was officially withdrawn in 1969. U.S. patent 3,503,060 from the RAMAC program is generally considered to be

3612-422: A removable IBM 1316 disk pack . Seven models of the 1311 were introduced during the 1960s. They were withdrawn during the early 1970s. Each IBM 1316 Disk Pack is 4 inches (100 mm) high, weighs 10 pounds (4.5 kg) and contains six 14-inch (360 mm) diameter disks, yielding 10 recording surfaces (the outer surfaces are not used). The 10 individual read/write heads are mounted on a common actuator within

3741-422: A removable IBM 1316 disk pack . Seven models of the 1311 were introduced during the 1960s. They were withdrawn during the early 1970s. Each IBM 1316 Disk Pack is 4 inches (100 mm) high, weighs 10 pounds (4.5 kg) and contains six 14-inch (360 mm) diameter disks, yielding 10 recording surfaces (the outer surfaces are not used). The 10 individual read/write heads are mounted on a common actuator within

3870-420: A single drive module, and two four drive modules for a total of nine drives. The drives are mounted in individual drawers that are unlatched and pulled out to access the disk pack. Because of their appearance they acquired the nickname of "Pizza Ovens". Only eight drives of the nine are available to the computer at any one time. The ninth drive is there for a spare for the user and can also be worked on "offline" by

3999-420: A single drive module, and two four drive modules for a total of nine drives. The drives are mounted in individual drawers that are unlatched and pulled out to access the disk pack. Because of their appearance they acquired the nickname of "Pizza Ovens". Only eight drives of the nine are available to the computer at any one time. The ninth drive is there for a spare for the user and can also be worked on "offline" by

Rainbow 100 - Misplaced Pages Continue

4128-449: A single drive with up to 8 heads and 1024 cylinders , limiting storage to a maximum of 67 MB . Third-party hard-disk controllers were also available, including a dual winchester support from CHS The base Rainbow system was capable of displaying text in 80×24- or 132×24-character format in monochrome only. The system could apply attributes to text including bolding, double-width, and double-height-double-width. The graphics option

4257-420: A single removable IBM 2316 disk pack which was similar in design to the 1316 but was taller as a result of increasing the number of disks from six to eleven. The 2316 disk pack containing the eleven 14-inch (360 mm) diameter disks yielded 20 recording surfaces. The drive access consisted of 20 individual R/W heads mounted on a common actuator which was moved in and out hydraulically and mechanically detented at

4386-420: A single removable IBM 2316 disk pack which was similar in design to the 1316 but was taller as a result of increasing the number of disks from six to eleven. The 2316 disk pack containing the eleven 14-inch (360 mm) diameter disks yielded 20 recording surfaces. The drive access consisted of 20 individual R/W heads mounted on a common actuator which was moved in and out hydraulically and mechanically detented at

4515-622: A small but important role in the creation of the FidoNet system. A computer club in St. Louis was in the process of setting up a BBS system using CBBS on CP/M when they learned that DEC would be giving the club a Rainbow 100 for free. The group planned on starting the BBS on this machine as soon as it arrived; but, when it did, they found that the Z80 did not have access to the serial ports. Casting about for

4644-464: A special casing to support their keyboard layout and language of the boot screen. On the 100A, the ROMs only supported three languages. The Rainbow did not have an ISA bus, so the typical 640 KB RAM limit didn't apply, with both models supporting a maximum RAM of over 800 KB . The "A" model was the first produced by Digital. The distinguishing characteristic of the "A" model from an end-user perspective

4773-437: A storage capacity of 20 million alphanumeric characters (120,000,000 bits) on 50 disks. In both models the disks are stacked vertically on a shaft rotating at 1200 rpm. Each side of each disk has 200 tracks divided into five sectors. Sectors 0–4 are on the top surface and 5–9 are on the bottom surface. Each sector holds either 178 or 200 characters. One to three forked-shaped access arms each contains two read/write heads, one for

4902-437: A storage capacity of 20 million alphanumeric characters (120,000,000 bits) on 50 disks. In both models the disks are stacked vertically on a shaft rotating at 1200 rpm. Each side of each disk has 200 tracks divided into five sectors. Sectors 0–4 are on the top surface and 5–9 are on the bottom surface. Each sector holds either 178 or 200 characters. One to three forked-shaped access arms each contains two read/write heads, one for

5031-711: A total 892 KB for the 100B or 828 KB for the 100A. The difference in max memory was due to the difference in initial memory configuration. The floppy disk drives, known as the RX50 , accepted proprietary 400 KB single-sided, quad-density 5¼-inch diskettes . Initial versions of the operating systems on the Rainbow did not allow for low-level formatting, requiring users to purchase RX50 media from Digital Equipment Corporation . The high cost of media ($ 5 per disk) led to accusations of vendor "lock-in" against Digital. However, later versions of MS-DOS and CP/M allowed formatting of diskettes. Formatting software for "normal" diskettes

5160-571: A very similar product, the IBM 355 , was announced for the IBM 650 RAMAC computer system. RAMAC stood for "Random Access Method of Accounting and Control". The first engineering prototype 350 disk storage shipped to Zellerbach Paper Company , San Francisco, in June 1956, with production shipment beginning in November 1957 with the shipment of a unit to United Airlines in Denver, Colorado. Its design

5289-411: A very similar product, the IBM 355 , was announced for the IBM 650 RAMAC computer system. RAMAC stood for "Random Access Method of Accounting and Control". The first engineering prototype 350 disk storage shipped to Zellerbach Paper Company , San Francisco, in June 1956, with production shipment beginning in November 1957 with the shipment of a unit to United Airlines in Denver, Colorado. Its design

Rainbow 100 - Misplaced Pages Continue

5418-498: Is 17 milliseconds (msec), and maximum is 34 msec. Maximum seek time per access group is 180 msec. The track size is 4985 bytes; with formatting information and alternate tracks, module capacity is stated as 112 MB. The 2302 attaches to IBM mainframes via a IBM 2841 Storage Control Unit. The IBM 2305 fixed head storage (a fixed-head disk drive sometimes incorrectly called a drum ) and associated IBM 2835 Storage Control were announced in 1970, initially to connect to

5547-498: Is 17 milliseconds (msec), and maximum is 34 msec. Maximum seek time per access group is 180 msec. The track size is 4985 bytes; with formatting information and alternate tracks, module capacity is stated as 112 MB. The 2302 attaches to IBM mainframes via a IBM 2841 Storage Control Unit. The IBM 2305 fixed head storage (a fixed-head disk drive sometimes incorrectly called a drum ) and associated IBM 2835 Storage Control were announced in 1970, initially to connect to

5676-401: Is 85 ms. Data transfer rate is 156  kB /s. Because the 2311 was to be used with a wide variety of computers within the 360 product line, its electrical interconnection was standardized. This created an opportunity for other manufacturers to sell plug compatible disk drives for use with IBM computers and an entire industry was born. The IBM 2314 Disk Access Storage Facility Model 1

5805-401: Is 85 ms. Data transfer rate is 156  kB /s. Because the 2311 was to be used with a wide variety of computers within the 360 product line, its electrical interconnection was standardized. This created an opportunity for other manufacturers to sell plug compatible disk drives for use with IBM computers and an entire industry was born. The IBM 2314 Disk Access Storage Facility Model 1

5934-425: Is rotated to release the bottom cover. Then the top of the 1311 drive is opened and the plastic shell lowered into the disk-drive opening (assuming it is empty). The handle is turned again to lock the disks in place and release the plastic shell, which is then removed and the drive cover closed. The process is reversed to remove a disk pack. The same methods are used for many later disk packs. There are seven models of

6063-425: Is rotated to release the bottom cover. Then the top of the 1311 drive is opened and the plastic shell lowered into the disk-drive opening (assuming it is empty). The handle is turned again to lock the disks in place and release the plastic shell, which is then removed and the drive cover closed. The process is reversed to remove a disk pack. The same methods are used for many later disk packs. There are seven models of

6192-447: The 1301 on June 5, 1961, 7070 and 7074 customers found it to be more attractive than the 7300. The 7300 uses the same technology as the IBM 350 , IBM 355 and IBM 1405 The IBM 1301 Disk Storage Unit was announced on June 2, 1961 with two models. It was designed for use with the IBM 7000 series mainframe computers and the IBM 1410 . The 1301 stores 28 million characters (168,000,000 bits) per module (25 million characters with

6321-447: The 1301 on June 5, 1961, 7070 and 7074 customers found it to be more attractive than the 7300. The 7300 uses the same technology as the IBM 350 , IBM 355 and IBM 1405 The IBM 1301 Disk Storage Unit was announced on June 2, 1961 with two models. It was designed for use with the IBM 7000 series mainframe computers and the IBM 1410 . The 1301 stores 28 million characters (168,000,000 bits) per module (25 million characters with

6450-600: The 1302 , with track formatting in accordance with S/360 DASD architecture rather than 7000 series architecture. It uses a non-removable module of 25 platters, of which 46 surfaces are used for recording. The 2302 Model 3 contains one module and the Model 4 two. There are two independent access mechanisms per module, one for the innermost 250 cylinders, and one for the outermost 250, tracks available to each access mechanism are called an access group . The access mechanism provides one read/write head per track. Average rotational delay

6579-548: The 1302 , with track formatting in accordance with S/360 DASD architecture rather than 7000 series architecture. It uses a non-removable module of 25 platters, of which 46 surfaces are used for recording. The 2302 Model 3 contains one module and the Model 4 two. There are two independent access mechanisms per module, one for the innermost 250 cylinders, and one for the outermost 250, tracks available to each access mechanism are called an access group . The access mechanism provides one read/write head per track. Average rotational delay

SECTION 50

#1732780162566

6708-581: The Computer History Museum , Mountain View, California and is now demonstrated to the public in the museum's Revolution exhibition. The IBM 353 , used on the IBM 7030 , was similar to the IBM 1301, but with a faster transfer rate. It has a capacity of 2,097,152 (2 ) 64-bit words or 134,217,728 (2 ) bits and transferred 125,000 words per second. A prototype unit shipped in late 1960 was the first disk drive to use one head per surface flying on

6837-455: The Computer History Museum , Mountain View, California and is now demonstrated to the public in the museum's Revolution exhibition. The IBM 353 , used on the IBM 7030 , was similar to the IBM 1301, but with a faster transfer rate. It has a capacity of 2,097,152 (2 ) 64-bit words or 134,217,728 (2 ) bits and transferred 125,000 words per second. A prototype unit shipped in late 1960 was the first disk drive to use one head per surface flying on

6966-503: The IBM 1316 Disk Pack introduced with the IBM 1311. The 2311 Model 1 attaches to most IBM mainframes through a 2841 Control Unit ; it attaches to the System/360 Model 25 thru a Disk Attachment Control which provides the function of the control unit. Disk packs are written in these attachments in IBM's count key data variable record length format. The 2311 models 11 or 12 are used when attached to an integrated control of

7095-436: The IBM 1316 Disk Pack introduced with the IBM 1311. The 2311 Model 1 attaches to most IBM mainframes through a 2841 Control Unit ; it attaches to the System/360 Model 25 thru a Disk Attachment Control which provides the function of the control unit. Disk packs are written in these attachments in IBM's count key data variable record length format. The 2311 models 11 or 12 are used when attached to an integrated control of

7224-541: The Intel 8088 respectively. The buses exchanged information via a shared 62 KB memory. When not executing 8-bit code, the Zilog Z80 was used for floppy disk access. The 8088 bus was used for control of all other subsystems, including graphics, hard disk access, and communications. While it may have been theoretically possible to load Z80 binary code into the Rainbow to execute alongside 8088 code, this procedure has never been demonstrated. The 8088 could be upgraded to

7353-603: The '80s on his DEC Rainbow. The DEC Rainbow can be seen in the films Ghostbusters , Beverly Hills Cop , and Firestarter . Michael Paré watches a TV commercial for "The Rainbow" in The Philadelphia Experiment . Winchester disk IBM manufactured magnetic disk storage devices from 1956 to 2003, when it sold its hard disk drive business to Hitachi . Both the hard disk drive (HDD) and floppy disk drive (FDD) were invented by IBM and as such IBM's employees were responsible for many of

7482-458: The 1311 disk drive. The first drive attached to a system is a "master drive" which contains the controller and can control a number of Model 2 "slave drives." The optional special features are: The master drives, Models 1, 3, 4, and 5, which contain extra power supplies and the control logic, are about a foot wider than the Model 2 slave drive. The IBM 2302 is the System/360 version of

7611-400: The 1311 disk drive. The first drive attached to a system is a "master drive" which contains the controller and can control a number of Model 2 "slave drives." The optional special features are: The master drives, Models 1, 3, 4, and 5, which contain extra power supplies and the control logic, are about a foot wider than the Model 2 slave drive. The IBM 2302 is the System/360 version of

7740-436: The 1410). Each module has 25 large disks and 40 user recording surfaces, with 250 tracks per surface. The 1301 Model 1 has one module, the Model 2 has two modules, stacked vertically. The disks spin at 1800 rpm. Data is transferred at 90,000 characters per second. A major advance over the IBM 350 and IBM 1405 is the use of a separate arm and head for each recording surface, with all the arms moving in and out together like

7869-436: The 1410). Each module has 25 large disks and 40 user recording surfaces, with 250 tracks per surface. The 1301 Model 1 has one module, the Model 2 has two modules, stacked vertically. The disks spin at 1800 rpm. Data is transferred at 90,000 characters per second. A major advance over the IBM 350 and IBM 1405 is the use of a separate arm and head for each recording surface, with all the arms moving in and out together like

SECTION 60

#1732780162566

7998-405: The 3330 product line: the 3333–11, 3330-11 and the 3336–11; the 3336-11 Disk Packs hold up to 200 MB (808x19x13,030 bytes). It is not possible to mix single and double density drives within a string. It is possible to field upgrade existing 3330 Models to Model 11, but this is a major task, as the drives had to be converted, and all the existing data had to be copied to the new media. The 3330

8127-405: The 3330 product line: the 3333–11, 3330-11 and the 3336–11; the 3336-11 Disk Packs hold up to 200 MB (808x19x13,030 bytes). It is not possible to mix single and double density drives within a string. It is possible to field upgrade existing 3330 Models to Model 11, but this is a major task, as the drives had to be converted, and all the existing data had to be copied to the new media. The 3330

8256-428: The 3333 contains a controller and two drives and it can control up to three attached 3330's for a maximum of eight drives in the string as shown in the illustration. The 3830 Model 2 can connect two 3333's for a maximum of 16 drives per storage control and the 3333 optionally has a string switch that enables it to be connected to two different storage controls. In 1973 IBM announced double density versions (-11 models) of

8385-428: The 3333 contains a controller and two drives and it can control up to three attached 3330's for a maximum of eight drives in the string as shown in the illustration. The 3830 Model 2 can connect two 3333's for a maximum of 16 drives per storage control and the 3333 optionally has a string switch that enables it to be connected to two different storage controls. In 1973 IBM announced double density versions (-11 models) of

8514-560: The 350 were announced in January 1959 and shipped later the same year. In 1984, the RAMAC 350 Disk File was designated an International Historic Landmark by The American Society of Mechanical Engineers. In 2002 at the Magnetic Disk Heritage Center, a team led by Al Hoagland began restoration of an IBM 350 RAMAC in collaboration with Santa Clara University . In 2005, the RAMAC restoration project relocated to

8643-421: The 350 were announced in January 1959 and shipped later the same year. In 1984, the RAMAC 350 Disk File was designated an International Historic Landmark by The American Society of Mechanical Engineers. In 2002 at the Magnetic Disk Heritage Center, a team led by Al Hoagland began restoration of an IBM 350 RAMAC in collaboration with Santa Clara University . In 2005, the RAMAC restoration project relocated to

8772-476: The 360/85 and 360/195 using the IBM 2880 Block Multiplexor Channel . The 2305 Drive was in much demand when the System 370 offered Virtual Storage , and these 2305s were often used for paging devices. They were used in this way on 3155, 3165, 3158, 3168, 3033, 4341, and 3081 (with special feature microcode.) The 2305 was also used for high activity small data sets such as catalogs and job queues. The 2305-1 has

8901-423: The 360/85 and 360/195 using the IBM 2880 Block Multiplexor Channel . The 2305 Drive was in much demand when the System 370 offered Virtual Storage , and these 2305s were often used for paging devices. They were used in this way on 3155, 3165, 3158, 3168, 3033, 4341, and 3081 (with special feature microcode.) The 2305 was also used for high activity small data sets such as catalogs and job queues. The 2305-1 has

9030-428: The IBM 1311) consisting of six platters that rotate as a single unit. The 2311 has ten individual read/write (R/W) heads mounted on a common actuator which moves in and out hydraulically and is mechanically detented at the desired track before reading or writing occurred. Each recording surface has 200 tracks plus three optional tracks which can be used as alternatives in case faulty tracks are discovered. Average seek time

9159-428: The IBM 1311) consisting of six platters that rotate as a single unit. The 2311 has ten individual read/write (R/W) heads mounted on a common actuator which moves in and out hydraulically and is mechanically detented at the desired track before reading or writing occurred. Each recording surface has 200 tracks plus three optional tracks which can be used as alternatives in case faulty tracks are discovered. Average seek time

9288-523: The Model 2 were $ 3,500 per month or $ 185,000 to purchase. The IBM 7631 controller cost an additional $ 1,185 per month or $ 56,000 to purchase. All models were withdrawn in 1970. The IBM 1302 Disk Storage Unit was introduced in September 1963. Improved recording quadrupled its capacity over that of the 1301, to 117 million 6-bit characters per module. Average access time is 165 ms and data can be transferred at 180 K characters/second, more than double

9417-466: The Model 2 were $ 3,500 per month or $ 185,000 to purchase. The IBM 7631 controller cost an additional $ 1,185 per month or $ 56,000 to purchase. All models were withdrawn in 1970. The IBM 1302 Disk Storage Unit was introduced in September 1963. Improved recording quadrupled its capacity over that of the 1301, to 117 million 6-bit characters per module. Average access time is 165 ms and data can be transferred at 180 K characters/second, more than double

9546-493: The RABIT TSR, which solved the problem generically for all Borland products). The DEC Rainbow 100 MS-DOS did support FAT formatted floppies. They were FAT12 format on 80-track, single-sided, quad-density 5.25" drives. The first two tracks were reserved for the boot loader, but didn't contain an MBR nor a BPB (MS-DOS 2.x and 3.10 on the Rainbow used a static in-memory BPB instead). The boot sector (track 0, side 0, sector 1)

9675-549: The Rainbow 100. Rock Point Community School on the Navajo reservation in Arizona commissioned a ROM chip for the Navajo language, enabling the school to create bilingual computer programs. Univation produced a number of products for the Rainbow as well. They offered add-in memory cards, hard disk controllers and LAN cards. The Univation disk interface was SASI/SCSI-1, but not software compatible with DEC's Winchester Disk option. It

9804-480: The Rainbow. There was an "ACT Winchester Option" available in Australia for which drivers have recently surfaced. Duncan MacDonald, Inc. offered a 20MB Floppy tape cartridge using a rebranded Cipher Data Products Model 525 floppy-tape cartridge tape drive. It used 3M DC600A tapes and could back up a 20MB RD31 in about 30 minutes. It included software to backup MS-DOS, CP/M and CCP/M partitions. List price in 1987

9933-448: The Rainbow. The Suitable Solutions Turbow-286 board could run a modified version of Windows 3.0 . Software bundled with DEC Rainbow floor model included: These documents come in booklets contained inside two hard case boxes, with the DEC logo. The Rainbow used a distinct version of MS-DOS, so it was not completely software- or hardware-compatible with the IBM PC or PC DOS. The expectation

10062-500: The Storage Facility. Other 2314 models came later: In 1969 IBM unbundled the facility into separate models allowing up to nine drives (eight on line) attached to a 2314 Storage Control : IBM introduced the IBM 3310 Direct Access Storage Device on January 30, 1979, for IBM 4331 midrange computers . Each drive had a capacity of 64.5 MB. The 3310 was a fixed-block architecture device, used on DOS/VSE and VM ,

10191-433: The Storage Facility. Other 2314 models came later: In 1969 IBM unbundled the facility into separate models allowing up to nine drives (eight on line) attached to a 2314 Storage Control : IBM introduced the IBM 3310 Direct Access Storage Device on January 30, 1979, for IBM 4331 midrange computers . Each drive had a capacity of 64.5 MB. The 3310 was a fixed-block architecture device, used on DOS/VSE and VM ,

10320-464: The System/360 Model 20 and the disk packs are written with a fixed sector format. The disk packs are not interchangeable between those written on the Model 1 and those written on the Models 11 or 12. The 2311 mechanism is largely identical to the 1311, but recording improvements allow higher data density. The 2311 stores 7.25  megabytes on a single removable IBM 1316 disk pack (the same type used on

10449-411: The System/360 Model 20 and the disk packs are written with a fixed sector format. The disk packs are not interchangeable between those written on the Model 1 and those written on the Models 11 or 12. The 2311 mechanism is largely identical to the 1311, but recording improvements allow higher data density. The 2311 stores 7.25  megabytes on a single removable IBM 1316 disk pack (the same type used on

10578-472: The VT220 style of this keyboard can clearly be seen in the layout of the enhanced 101-key keyboard adopted by IBM in 1985. Third-party upgrades were also available, including an 80286 (286) processor upgrade (Turbow-286), a 3.5-inch disk adapter kit (IDrive), and a battery-backed clock chip (ClikClok), all from Suitable Solutions . In 1984, the first computer support for Native American languages began with

10707-431: The boot menu due to updated firmware. The hardware changes included bigger firmware stored on two 27128 (16 KB) ROMs and an improved case fan/power supply. The firmware allowed selection of the boot screen language and keyboard layout, eliminating the need to switch ROM. The "B" model also allowed remapping of hardware interrupts to be more compatible with MS-DOS. The B model also improved the memory expansion slot to allow

10836-509: The commercial software that could be run. Towards the end of the Rainbow's life, users were able to run some IBM PC-compatible MS-DOS software using an emulation application called Code Blue , though it emulated only the IBM PC's BIOS and some of the hardware, so programs that accessed the video cards directly would not work very well. MS-DOS compatibility was added late in the design, so hardware interrupts and MS-DOS software interrupts overlapped. One DEC documentation pack for developers included

10965-407: The desired track before reading or writing occurred. Each recording surface has 200 tracks. Access time was initially the same as the 2311, but later models were faster as a result of improvements made in the hydraulic actuator. Data transfer rate was doubled to 310 kB/s. The original Model 1 consists nine disk drives bundled together with one price; separately shipped was a storage control unit,

11094-407: The desired track before reading or writing occurred. Each recording surface has 200 tracks. Access time was initially the same as the 2311, but later models were faster as a result of improvements made in the hydraulic actuator. Data transfer rate was doubled to 310 kB/s. The original Model 1 consists nine disk drives bundled together with one price; separately shipped was a storage control unit,

11223-399: The disk drive which moves in and out hydraulically and is mechanically detented at the desired track before reading or writing occurs. The disks spin at 1500 rpm. Each recording surface has 100 tracks with 20 sectors per track. Each sector stores 100 characters. The disk pack is covered with a clear plastic shell and a bottom cover when not in use. A lifting handle in the top center of the cover

11352-399: The disk drive which moves in and out hydraulically and is mechanically detented at the desired track before reading or writing occurs. The disks spin at 1500 rpm. Each recording surface has 100 tracks with 20 sectors per track. Each sector stores 100 characters. The disk pack is covered with a clear plastic shell and a bottom cover when not in use. A lifting handle in the top center of the cover

11481-536: The disk. This was remedied later by placing a red arrow on the diskette slots and on the top of the diskettes to indicate which side of the diskette to be inserted into each diskette drive. Digital Equipment Corporation produced a Winchester disk controller capable of controlling hard disks compatible with the ST-506 interface. The controller, based on the Western Digital WD1010 chip, was limited to

11610-401: The faster NEC V20 chip. This gave about 10-15% speed improvement, but required changes to the system's ROMs to fix two timing loops. The 100A model shipped with 64 KB memory on the motherboard, while the 100B had 128 KB memory on the motherboard. Daughterboards were available from Digital Equipment Corporation that could increase system memory with up to an additional 768 KB for

11739-595: The fundamental patent for disk drives. This first-ever disk drive was initially cancelled by the IBM Board of Directors because of its threat to the IBM punch card business but the IBM San Jose laboratory continued development until the project was approved by IBM's president. The 350's cabinet is 60 inches (150 cm) long, 68 inches (170 cm) high and 29 inches (74 cm) wide. The RAMAC unit weighs about one ton, has to be moved around with forklifts, and

11868-477: The fundamental patent for disk drives. This first-ever disk drive was initially cancelled by the IBM Board of Directors because of its threat to the IBM punch card business but the IBM San Jose laboratory continued development until the project was approved by IBM's president. The 350's cabinet is 60 inches (150 cm) long, 68 inches (170 cm) high and 29 inches (74 cm) wide. The RAMAC unit weighs about one ton, has to be moved around with forklifts, and

11997-475: The hard and soft vectors. The Rainbow 100A initially only supported 256 KB of RAM total, but the limitation in the memory expansion slot was later worked around with a special adapter card, though the maximum was limited to 828 KB. The "B" model followed the "A" model, and introduced a number of changes. The "B" model featured the ability to boot from a hard disk (referred to as the Winchester drive) via

12126-478: The innovations in these products and their technologies. The basic mechanical arrangement of hard disk drives has not changed since the IBM 1301 . Disk drive performance and characteristics are measured by the same standards now as they were in the 1950s. Few products in history have enjoyed such spectacular declines in cost and physical size along with equally dramatic improvements in capacity and performance. IBM manufactured 8-inch floppy disk drives from 1969 until

12255-478: The innovations in these products and their technologies. The basic mechanical arrangement of hard disk drives has not changed since the IBM 1301 . Disk drive performance and characteristics are measured by the same standards now as they were in the 1950s. Few products in history have enjoyed such spectacular declines in cost and physical size along with equally dramatic improvements in capacity and performance. IBM manufactured 8-inch floppy disk drives from 1969 until

12384-417: The mid-1980s, but did not become a significant manufacturer of smaller-sized, 5.25- or 3.5-inch floppy disk drives (the dimension refers to the diameter of the floppy disk, not the size of the drive). IBM always offered its magnetic disk drives for sale but did not offer them with original equipment manufacturer (OEM) terms until 1981. By 1996, IBM had stopped making hard disk drives unique to its systems and

12513-417: The mid-1980s, but did not become a significant manufacturer of smaller-sized, 5.25- or 3.5-inch floppy disk drives (the dimension refers to the diameter of the floppy disk, not the size of the drive). IBM always offered its magnetic disk drives for sale but did not offer them with original equipment manufacturer (OEM) terms until 1981. By 1996, IBM had stopped making hard disk drives unique to its systems and

12642-526: The only S/370 operating systems that supported FBA devices. The IBM 3330 Direct Access Storage Facility, code-named Merlin , was introduced in June 1970 for use with the IBM System/370 and the IBM System 360 /195. The original announcement included the 3330 Model 1, with two drives, and the 3330 Model 2, with only one drive. The 3330 has removable disk packs, similar to its predecessors, and

12771-403: The only S/370 operating systems that supported FBA devices. The IBM 3330 Direct Access Storage Facility, code-named Merlin , was introduced in June 1970 for use with the IBM System/370 and the IBM System 360 /195. The original announcement included the 3330 Model 1, with two drives, and the 3330 Model 2, with only one drive. The 3330 has removable disk packs, similar to its predecessors, and

12900-485: The packs hold 100 MB (404×19×13,030 bytes). Access time is 30 ms and data transfers at 806 kB/s. A major advance introduced with the 3330 is the use of error correction , which makes the drives more reliable and reduces costs because small imperfections in the disk surface can be tolerated. The circuitry can correct error bursts up to 11 bits long through use of fire codes . The initial configuration consists of one storage control unit (3830 Model 1) bolted to

13029-485: The packs hold 100 MB (404×19×13,030 bytes). Access time is 30 ms and data transfers at 806 kB/s. A major advance introduced with the 3330 is the use of error correction , which makes the drives more reliable and reduces costs because small imperfections in the disk surface can be tolerated. The circuitry can correct error bursts up to 11 bits long through use of fire codes . The initial configuration consists of one storage control unit (3830 Model 1) bolted to

13158-436: The physical sectors in order numbered 1 to 10 on each track after the reserved tracks, but the logical sectors from 1 to 10 were stored in physical sectors 1, 6, 2, 7, 3, 8, 4, 9, 5, 10. This makes it hard to create Rainbow disk images since all existing tools assume there will be an MBR with a BPB, and required various hacks to make up for the lack of on-disk BPB. The DEC Rainbow 100 had no general expansion bus. Instead, it had

13287-407: The power for the monochrome monitor was supplied through the single video cable, eliminating the need for a separate power cable. The Rainbow 100 and the other two microcomputers which DEC announced at the same time ( DECmate II and Pro-350 ) had two quirks that annoyed conservative users. The LK201 keyboard used a new layout that made some Teletype Model 33 and VT100 users unhappy. However,

13416-508: The same box, but it cost $ 750 which was prohibitively expensive so few Rainbows had Ethernet. While the software incompatibilities were bad, the lack of expansion hardware flexibility was worse, and the inability to use ISA cards, despite their flaws at the time, played a significant role in the Rainbow fading from the scene. The Multi Emulator Super System can run the Rainbow-specific Windows 1.0. The Rainbow 100 played

13545-482: The speed of the 1301. There are two access mechanisms per module, one for the inner 250 cylinders and the other for the outer 250 cylinders. As with the 1301, there is a Model 2 which doubles the capacity by stacking two modules. The IBM 1302 Model 1 leased for $ 5,600 per month or could be purchased for $ 252,000. Prices for the Model 2 were $ 7,900 per month or $ 355,500 to purchase. The IBM 7631 controller cost an additional $ 1,185 per month or $ 56,000 to purchase. The 1302

13674-482: The speed of the 1301. There are two access mechanisms per module, one for the inner 250 cylinders and the other for the outer 250 cylinders. As with the 1301, there is a Model 2 which doubles the capacity by stacking two modules. The IBM 1302 Model 1 leased for $ 5,600 per month or could be purchased for $ 252,000. Prices for the Model 2 were $ 7,900 per month or $ 355,500 to purchase. The IBM 7631 controller cost an additional $ 1,185 per month or $ 56,000 to purchase. The 1302

13803-443: The surface of the disk on a thin layer of air. This allows them to be much closer to the recording surface, which greatly improves performance. The 1301 connects to the computer via the IBM 7631 File Control. Different models of the 7631 allow the 1301 to be used with a 1410 or 7000 series computer, or shared between two such computers. The IBM 1301 Model 1 leased for $ 2,100 per month or could be purchased for $ 115,500. Prices for

13932-443: The surface of the disk on a thin layer of air. This allows them to be much closer to the recording surface, which greatly improves performance. The 1301 connects to the computer via the IBM 7631 File Control. Different models of the 7631 allow the 1301 to be used with a 1410 or 7000 series computer, or shared between two such computers. The IBM 1301 Model 1 leased for $ 2,100 per month or could be purchased for $ 115,500. Prices for

14061-414: The top of the disk and the other for the bottom of the same disk. The access arms are mounted on a carriage alongside the disk array. During a seek operation an access arm moved, under electronic control, vertically to seek a disk 0–49 and then horizontally to seek a track 0–199. Ten sectors are available at each track. It takes about 10 ms to read or write a sector. The access time ranges from 100ms to

14190-414: The top of the disk and the other for the bottom of the same disk. The access arms are mounted on a carriage alongside the disk array. During a seek operation an access arm moved, under electronic control, vertically to seek a disk 0–49 and then horizontally to seek a track 0–199. Ten sectors are available at each track. It takes about 10 ms to read or write a sector. The access time ranges from 100ms to

14319-422: Was $ 1200. In addition, Duncan MacDonald, Inc. provided MFM disks in 20MB, 40MB, and 67MB that used the same disks that DEC sold for much more, and provided a nice steel cabinet with power supply so the Rainbow's power supply wouldn't be overtaxed by the power requirements of larger disks. Here are the various hardware options that were available for the Rainbow (country kits are not yet listed): Data compiled from

14448-548: Was Z80 code beginning with DI 0xF3 . The 8088 bootstrap was loaded by the Z80. Track 1, side 0, sector 2 starts with the Media/FAT ID byte 0xFA . Unformatted disks use 0xE5 instead. The file system starts on track 2, side 0, sector 1. There are 2 copies of the FAT and 96 entries in the root directory. In addition, there is a physical to logical track mapping to effect a 2:1 sector interleaving. The disks were formatted with

14577-421: Was a user-installable module that added graphics and color display capabilities to the Rainbow system. The Graphic module was based on a NEC 7220 graphic display controller (GDC) and an 8×64 KB DRAM video memory. Due to the design of the graphics system, the Rainbow was capable of controlling two monitors simultaneously, one displaying graphics and another displaying text. The base Rainbow system generates

14706-409: Was also made available by third parties. Of note was the single motor used to drive both disk drives via a common spindle, which were arranged one on top of the other. That meant that one disk went underneath the first but inserted upside-down. This earned the diskette drive the nickname "toaster". The unusual orientation confused many first-time users, who would complain that the machine would not read

14835-459: Was based on a design by Xebec . C.H.S. created a dual-Winchester controller for the DEC Rainbow as well. It was compatible enough with the DEC's disk controller that one could boot off it on the 100B/100+/190. Like DEC's offering, it was based on Western Digital's WD1010 chip. However, additional drivers were needed to access the second hard drive. REC of Switzerland created a SCSI card for

14964-549: Was for programs to target the MS-DOS interface and not the underlying hardware. However, many significant commercial software products were writing directly to the hardware for a variety of reasons, including performance. After the Compaq Portable and other clones, the market expectation was that all MS-DOS versions would be fully IBM PC compatible . Later, Microsoft would stop licensing distinctive OEM versions and sell standardized MS-DOS 5.0 at retail. While "Code Blue" did

15093-468: Was frequently transported via large cargo airplanes. According to Currie Munce, research vice president for Hitachi Global Storage Technologies (which acquired IBM's storage business), the storage capacity of the drive could have been increased beyond five million characters, but IBM's marketing department at that time was against a larger capacity drive, because they didn't know how to sell a product with more storage. Nonetheless, double capacity versions of

15222-468: Was frequently transported via large cargo airplanes. According to Currie Munce, research vice president for Hitachi Global Storage Technologies (which acquired IBM's storage business), the storage capacity of the drive could have been increased beyond five million characters, but IBM's marketing department at that time was against a larger capacity drive, because they didn't know how to sell a product with more storage. Nonetheless, double capacity versions of

15351-599: Was introduced on April 22, 1965, one year after the System/360 introduction. It was used with the System/360 and the System/370 lines. With the Two Channel Switch feature it could interface with two 360/370 channels. The 2314 Disk access mechanism was similar to the 2311, but further recording improvements allowed higher data density. The 2314 stored 29,176,000 characters (200×20×7294 bytes per track) on

15480-413: Was introduced on April 22, 1965, one year after the System/360 introduction. It was used with the System/360 and the System/370 lines. With the Two Channel Switch feature it could interface with two 360/370 channels. The 2314 Disk access mechanism was similar to the 2311, but further recording improvements allowed higher data density. The 2314 stored 29,176,000 characters (200×20×7294 bytes per track) on

15609-443: Was motivated by the need for real time accounting in business. The 350 stores 5 million 6-bit characters (3.75 MB). It has fifty-two 24- inch (610  mm ) diameter disks of which 100 recording surfaces are used, omitting the top surface of the top disk and the bottom surface of the bottom disk. Each surface has 100 tracks. The disks spin at 1200 rpm . Data transfer rate is 8,800 characters per second. An access mechanism moves

15738-443: Was motivated by the need for real time accounting in business. The 350 stores 5 million 6-bit characters (3.75 MB). It has fifty-two 24- inch (610  mm ) diameter disks of which 100 recording surfaces are used, omitting the top surface of the top disk and the bottom surface of the bottom disk. Each surface has 100 tracks. The disks spin at 1200 rpm . Data transfer rate is 8,800 characters per second. An access mechanism moves

15867-465: Was offering all its HDDs as an OEM. IBM uses many terms to describe its various magnetic disk drives, such as direct-access storage device (DASD), disk file and diskette file. Here, the current industry standard terms, hard disk drive (HDD) and floppy disk drive (FDD), are used. The IBM 350 disk storage unit, the first disk drive, was announced by IBM as a component of the IBM 305 RAMAC computer system on September 14, 1956. Simultaneously

15996-465: Was offering all its HDDs as an OEM. IBM uses many terms to describe its various magnetic disk drives, such as direct-access storage device (DASD), disk file and diskette file. Here, the current industry standard terms, hard disk drive (HDD) and floppy disk drive (FDD), are used. The IBM 350 disk storage unit, the first disk drive, was announced by IBM as a component of the IBM 305 RAMAC computer system on September 14, 1956. Simultaneously

16125-404: Was that the earlier firmware did not support booting from a hard disk. Other distinguishing hardware features included the three 2764 (8 KB) ROM chips holding the system firmware and the case fan/power supply combinations. In addition, the 100A was unable to move its hardware interrupt vectors to avoid the conflict with MS-DOS soft INT 21, etc. DOS had to take unusual actions to distinguish between

16254-474: Was withdrawn in 1983. The IBM 3340 and 3344 have similar characteristics. However, only a 3340 can serve as head of string; there are no A model 3344 drives, and a 3344 must be attached to a 3340 A model as head of string. The IBM 3340 Direct Access Storage Facility, code-named Winchester , was introduced in March 1973 for use with IBM System/370 . Three models were announced, the 3340-A2 with two drives and

16383-422: Was withdrawn in 1983. The IBM 3340 and 3344 have similar characteristics. However, only a 3340 can serve as head of string; there are no A model 3344 drives, and a 3344 must be attached to a 3340 A model as head of string. The IBM 3340 Direct Access Storage Facility, code-named Winchester , was introduced in March 1973 for use with IBM System/370 . Three models were announced, the 3340-A2 with two drives and

16512-483: Was withdrawn in February 1965. The IBM 1311 Disk Storage Drive was announced on October 11, 1962, and was designed for use with several medium-scale business and scientific computers. The 1311 is about the size and shape of a top-loading washing machine and stores 2 million characters (12,000,000 bits) (or, in so-called "Load Mode" on an IBM 1401, a sector can hold 90 7-bit characters, or 12,600,000 bits total ) on

16641-427: Was withdrawn in February 1965. The IBM 1311 Disk Storage Drive was announced on October 11, 1962, and was designed for use with several medium-scale business and scientific computers. The 1311 is about the size and shape of a top-loading washing machine and stores 2 million characters (12,000,000 bits) (or, in so-called "Load Mode" on an IBM 1401, a sector can hold 90 7-bit characters, or 12,600,000 bits total ) on

#565434