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62-634: Although an XE-styled drive was shown several times during 1985 and 1986, production waited while leftover inventories of the Atari 1050 were sold off. By the time these ran out late in 1986, interest in the 8-bit line had waned and a new model was not put into production. At the same time, the success of the Nintendo Entertainment System (NES) prompted Atari to repackage their 65XE as the Atari XEGS video game console , boasting it could be expanded to

124-468: A complete computer with the addition of a keyboard and disk drive. Nintendo sued, noting that Atari had no disk drives to sell, forcing Atari to rush the drive to market in June 1987 even though the software was not ready. The XF551 is generally considered the best of Atari's drive offerings; not only does it store three times as much data as the 1050, it is twice as fast and almost silent in operation. Its release

186-454: A direct replacement for the 1050 rather than the major upgrade it was intended to be. DOS XE did not ship until 1988/89, by which time the same modes were already supported by a variety of 3rd party solutions like SpartaDOS . Nevertheless, shipping DOS 2.5 with the drives for over a year led to significant confusion in the market. The drive was otherwise very well received. It was "eerily silent during operation", so much so that reviews noted it

248-411: A disk required another notch to be punched in the disk, or the drive to be slightly modified to ignore the notch. When used in 810 compatible mode, the drive formatted disks with 40 tracks and 18 sectors per track, for a total of 720 sectors per disk. Each sector held 128 bytes, for a total storage of 92,160 bytes/disk (90 kB). This was the normal FM encoded single-density format used by most machines of

310-418: A half-height mechanism, 1 + 5 ⁄ 8 inches (41.3 mm) tall, compared to the 810's full-height 3 + 1 ⁄ 4 inches (82.6 mm). Its new case was designed by Tom Palecki. In keeping with most of Tandon's mechanisms, a rotating arm on the front of the drive was used to lock the floppy into place. The drive also had its own read/write LED beside the down position of the latch. The power switch

372-516: A largely identical mechanism from World Storage Technology. Production returned to Singapore for the final run using Tandon from October 1985 to December 1985. MOS Technology 6507 The 6507 (typically " sixty-five-oh-seven " or " six-five-oh-seven ") is an 8-bit microprocessor from MOS Technology, Inc. It is a version of their 40-pin 6502 packaged in a 28-pin DIP , making it cheaper to package and integrate in systems. The reduction in pin count

434-452: A new drive from Atari within the next half year". This prediction came true; when the 1200XL finally reached the market in June 1983, it was accompanied by the new Atari 1050. The disk mechanism moved from the original Tandon used in the 810 to the new "thinline" design that was slightly shorter and led to a more compact case. It offered the new "enhanced" or "dual density" option that improved formatted capacity to 130 kB, and replaced

496-524: A new line of peripherals matching the styling of the new machine. This included the Atari 1050 , a new disk drive that was built around the double-density MFM encoding standard that provided up to 180 kB of storage. For reasons unknown, Atari's DOS for the machine did not support the double-density format, instead it used a new format known alternately as "enhanced density" or "dual density" with 130 kB. Several 3rd party DOS products emerged that fully supported double-density, as well as new drives like

558-470: A relatively fast 8.33 MHz. The controller was paired with the then-standard Western Digital FD1772 floppy disk controller, a late-model version of WD's drive controllers that implemented almost all of the required circuitry in a single 28-pin chip and thereby lowered the total cost of implementation. Previous to the XF551, users would generally use both sides of a floppy disk by formatting one side, flipping

620-451: A repackaged Atari 65XE and would run existing 8-bit games. As part of the XEGS launch, Atari boasted about its large library of software as well as its ability to be used as a true computer with the supplied keyboard and optional peripherals including a floppy drive. By this point, stocks of the 1050 had already run out. This led to about six months where no official Atari drives were available for

682-470: A shame so many newer Atari users have been saddled with it." By this time, increasing sales of the 400 and 800 and the failure of a new drive to appear from Atari led to a thriving market for third-party drives and alternative DOSes, many of which provided true double-density support using the format originally introduced on the 815. An August 1984 review in Antic compared the 1050 with four 3rd party drives and

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744-406: A thriving market for 3rd party DOSes which had long supported double-density modes and the higher transfer speeds. Among these was DOS XL , introduced in 1983 by Optimized Systems Software (OSS), authors of the original Atari DOS. Atari contracted OSS to produce a new version, initially known as ADOS, which added double-sided support to its existing double-density and high-speed features. Prior to

806-405: Is achieved by reducing the address bus from 16 bits to 13 (limiting the available memory range from 64   KB to 8   KB) and removing a number of other pins used only for certain applications. To do this, A15 to A13 and some other signals such as the interrupt lines are not accessible. As a result, it can only address 8   KB of memory, which for some applications at the time (1975)

868-466: The 650x architecture , use either the standard 6502 or extended versions of it, in order to allow for more memory. By the time the 6502 line was becoming widely used around 1980, ROM and RAM semiconductor memory prices had fallen to the point where the 6507 was no longer a worthwhile simplification. Its use in new designs ceased at that point, though the Atari 2600 that contains it continued to be sold into

930-550: The Indus GT that offered double-density from the start, along with additional features and improved performance. In 1983, Commodore International sparked off a price war in the home computer market by repeatedly lowering the price of its VIC-20 and Commodore 64 (C64) lines in order to undercut the TI-99/4A . Atari had recently introduced the Atari 1200XL at a higher price point, and its lineup could not be produced profitably at

992-666: The Intel 8048 microcontroller . The 8048 included internal RAM and ROM and thus greatly simplified the overall design of the interface. The Tramiels took the CR and repackaged it to match the silver-grey styling of the XE and ST line. While introducing the XE's at the January 1985 Consumer Electronics Show , the company previewed the design as the XF521. It was rumored it would also support true double-density mode. When

1054-459: The 1050 it replaced, but overall similar. It connected to the computer or XEGS using the SIO port, with two ports on the back, in and out, to allow it to be daisy chained to other peripherals. The back also had the jack for the power supply , the power switch, and a DIP switch that allowed the drive to be numbered 1 through 4. When operating in legacy modes to read or write to disks from the 810 or 1050,

1116-560: The 2600, the system is further limited by the design of the ROM cartridge slot, which only allows for 4   KB of the external memory to be addressed. The other 4   KB is reserved for the internal RAM and I/O chips, using a minimal-cost partial decoding technique that causes the RAM and peripheral device registers to appear at multiple aliased addresses throughout the 4   K address space. Most other machines, notably home computers based on

1178-588: The 400 and 800 series. Ultimately Atari introduced only one new computer model, named 1200XL . When it was introduced at the Winter Consumer Electronics Show in December 1982, it was shown with the new Atari 1010 cassette deck , and the 1020 plotter and 1025 printers. There was no sign of a new floppy drive, and one reviewer noted that when he went looking all he could find was the "old model 810 clunkers", speculating that "we will be seeing

1240-491: The 810 and 815. The 810 was an entry-level model, supporting only single-density FM encoding at 90 kB total storage. The 815 used two double-density MFM encoding drives in a single large housing, each drive offering 180 kB of storage. For reasons unknown, the 815 was produced only in small numbers starting in 1980 and then abandoned, leaving the platform only with the 810 which were described by InfoWorld as "noisy, slow and inefficient." In April 1982, Atari began

1302-410: The 810 in the market. To take advantage of the new enhanced density mode, a new version of Atari DOS was needed, 3.0. This was not available at launch, and the early examples shipped with DOS 2.0S instead, meaning they could not take advantage of the new features. The required DOS 3.0 eventually shipped several months later. However, it used an entirely new format using 1 kB "blocks" rather than

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1364-456: The 810; the 1050 was beaten by all but the 810 in both capacity and speed. The 1050 was described as "a no-frills drive", especially compared to the Rana 1000 and Indus GT , which offered double-density, various high-speed modes, front-panel displays, and many other features. The lack of double density support was described as "a mystery". The problems with DOS 3.0 were finally addressed in 1984 with

1426-408: The 815 packaged two drives in a single case, both supporting a double-density MFM encoding format of 180 kB. Small numbers of the 815 began shipping in June 1980, but mass production never started. Nevertheless, this brief introduction set the standard for double-density drives that other companies would later support. During the introduction of the Atari 1200XL in 1982, the company introduced

1488-551: The CPU to indicate if a read or write memory (or MMIO device) access is being performed (the R/W pin). There is no IRQ or NMI pin on the processor. The RDY pin is not included on all other 28-pin cut-down versions of the 6502. Within the Atari 2600, RDY is used to synchronise the CPU to the television video lines. This function is essential for the 'racing the beam' method used by the 6502 and Atari Television Interface Adaptor chip to generate

1550-513: The Doubler and Happy systems, offering much better performance from such systems. Both were also supported by most other 3rd party DOSes on the platform. The new XL series machines were launched into the middle of a price war between Commodore International and Texas Instruments , which quickly drove everything but the Commodore 64 and Apple II from the market. Sales of the 8-bits plummeted. At

1612-459: The Nintendo lawsuit, Atari claimed the only holdup on the new drive was that the documentation for the new DOS was not ready. When the lawsuit was launched, Atari put the drive on the market immediately in June 1987, shipping it with the existing Atari DOS 2.5. This was a success, as it did result in the lawsuit being dropped. However, DOS 2.5 lacked support for the new modes, which essentially made it

1674-523: The Tramiels took over the company they found huge stocks of unsold 1050s, and repeatedly delayed the XF521 while selling these off. By the time the stocks of these drives finally dwindled in 1986, the ST was selling strongly and the company had lost interest in the 8-bit line. Any mention of the XF521 disappeared. In October 1985, Nintendo introduced the Nintendo Entertainment System to North America. By late 1986 it

1736-587: The XF551 Enhancer appeared, a modification that allowed the drive to ignore the timing hole and write to either side of the disk. Most of the drives sold used a Mitsumi Electric mechanism, although a small number of later models replaced this with one from Chinon Industries . They can be distinguished as the Mitsumi version has a rectangular LED on the front while the Chinon version is round. The Chinon versions also used

1798-428: The XF551 ran at the industry standard 300 RPM. This caused problems for a small number of programs whose copy protection relied on accurately timing the drive. One design feature of DOS XE was that it always wrote files to side one of the floppy until it ran out of room. This meant the disks could be inserted in older drives also being run with DOS XE, or compatible double-density 3rd party DOSes, and at least read

1860-467: The birth of the 130XE". By the late 1980s, sales of the XE series were primarily to low-cost markets like eastern Europe and South America. These markets were so cost-sensitive that even the low price of the XF551 was too much for most users, and the most common storage mechanism was the XC12 cassette tape system. The entire 8-bit series was eventually discontinued in 1992. The XF551 was slightly smaller than

1922-542: The board , Irving Gould , and left the company. After spending some time looking for ways to re-enter the field, in July he arranged a deal to buy Atari from its owners, Warner Communications , for no cash and several million in promissory notes . Attempting to bring the company back to some semblance of profitability, the new management laid off whole divisions while working to bring their new Atari ST , to market as soon as possible. During this period many advanced projects within

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1984-409: The chip identifier are part of the silicon layers, and the final digit is in the metallisation layer. Micro-photography of the 6502 and 6507 shows this difference. The 6507 is widely used in two applications: the best-selling Atari 2600 video game console and peripherals for the Atari 8-bit computers including the 850 Serial & Parallel Interface, and the 810 and 1050 disk drives. In

2046-446: The company were cancelled. This included Atari's own 32-bit efforts and several advanced game consoles . Warehouses filled with stocks of the 8-bit line were sold off at fire-sale prices pending the introduction of cost-reduced models, the XE series. Atari had already been working on several upgrades to the 1050 series, including the 1050CR, for cost-reduced. This replaced the original custom MOS 6507 -based interface card with one using

2108-494: The disk over, and formatting the second, the so-called " flippy disk ". This presented a potential problem with the new drive; if a user flipped the disk and formatted using the default double-sided format, any data on the other side would be erased. To prevent this, the system only allowed formatting if the disk's timing hole was in the correct "up" position, otherwise it would only format in the older single-sided formats. For those that needed to make flippys for use with other drives,

2170-551: The early 1990s, as it was not discontinued until January 1, 1992. However, late-model Atari 2600 consoles do not necessarily contain a discrete 6507 chip. The 6507 uses a 28-pin configuration, with 13 address pins (A0..A12) and 8 data pins (D0..D7). The seven remaining pins are used for power (Vss, Vcc), the CPU timing clock (φ0, φ2), to reset the CPU (the /RES pin), to request a CPU wait state during its next memory read access (the RDY pin), and for

2232-483: The entire 8-bit line plummeted. When Jack Tramiel purchased Atari in 1984 there were warehouses filled with unsold 1050s, which delayed production of a replacement. It was not until 1987 that the Atari XF551 was introduced, offering both double-density and double-sided capabilities and a double-speed transfer mode. When the 8-bit series was first announced in 1978 it was often shown with two floppy disk drive systems,

2294-405: The existing stock on the market for fire-sale prices while they developed new very-low-cost versions of the machines. These emerged as the XE series, which were presented at the January 1985 Consumer Electronics Show, along with a restyled 1050 called the XF521. They continued to show the new drive through 1985 and 1986, but it disappeared without ever shipping. By 1986 the new Atari ST series

2356-412: The files on that side. Atari 1050 The Atari 1050 is a floppy disk drive for Atari 8-bit computers released in June 1983. It is compatible with the 90 kB single-density mode of the original Atari 810 it replaced, and added a new "enhanced" or "dual density" mode that provided 130 kB. Based on a half-height Tandon mechanism, it was smaller than the 810 and matched the styling of

2418-454: The introduction of the IBM PC , drives using the standard 34-bit ribbon cable had proliferated. This allowed internal mechanisms to be easily swapped. Earlier Atari drives used a customized controller that communicated with the host computer's Atari SIO bus using a MOS 6507 running at 500 kHz. For historical reasons, these drives used a 19.2 kbps speed to transfer data, although this

2480-458: The introduction of the "long awaited" DOS 2.5. This returned to the 2.0-style formatting even for enhanced density, allowing DOS 2 and 2.5 users to swap disks as long as they were in single-density format. By this time, most of the 3rd party DOSes had already added support for enhanced mode. As was the case for the 810 before it, the 1050 was the subject of a number of 3rd party upgrades that improved performance in various ways. Notable among these

2542-414: The late 1970s. Normally, when used with MFM encoding for double-density, the number of bytes per sector was doubled to 256 and the layout was otherwise unchanged. Instead, Atari's format retained the original 128 byte sectors and increased the number per track to 26, thereby providing 40 x 26 x 128 = 133,120 bytes per side, 130 kB. While Atari's documentation referred to this as double density, users used

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2604-491: The line, and it appeared the company was in no hurry to introduce the XF521. Nintendo sued Atari for false advertising , noting that Atari claimed the system supported a floppy but did not actually have drives for sale. At some point during this period, Atari decided to completely redesign the drive. The computer market was already well into the conversion from 5.25 to 3.5-inch disks, and 5.25 double-density double-sided drives were now commonplace and inexpensive. Moreover, after

2666-417: The new 600XL and 800XL machines. By the time it was available, a wide variety of third party drives had been introduced for the 8-bit platform, many of which were faster and offered true double-density support for 180 kB. The lack of double-density support on the 1050 was a mystery to onlookers at the time, as the hardware had full support for this format. The launch was further marred by releasing it with

2728-463: The new drive, which operated at higher speeds and had more features, the 6507 was replaced by the Intel 8040 , microcontrollers that included ROM and RAM on the same chip and thus allowed a great simplification of the controller. The 8040 versions did not have enough ROM for the entire driver, so later models moved to the 8050 with 4 kB for a further simplification. These chips, originally introduced in 1976, were now available for pennies and ran at

2790-420: The older Atari DOS 2.0S, S for "single", which did not support the 130 kB capacity. Atari replaced 2.0 with DOS 3.0 which supported the enhanced density mode, but used an entirely new format that was incompatible with earlier disks. The release of DOS 2.5 in 1985 finally addressed these issues. The 1050 was launched directly into the rise of the Commodore 64 and the videogame crash of 1983 when sales of

2852-445: The process of designing an improved version of the 8-bit series, which were to be known as the 1000 and 1000X. Among the changes was a new design language from Regan Cheng using off-white and black plastics with brushed metal overlay on switches and other fixtures. Along with the machines, a new line of peripherals would be released with matching styling, numbered in the 1000's in the same fashion that earlier devices had been numbered in

2914-549: The rapidly falling market prices. Atari eventually introduced lower-cost models, the 600XL and 800XL, but these were repeatedly delayed and did not reach market until late in 1983, too late to have an impact. Combined with the effects of the video game crash of 1983 , the company was soon losing over a million dollars a day. The success of the C64 did not save Commodore from problems of its own. In January 1984, Commodore president Jack Tramiel got into some sort of argument with chairman of

2976-624: The same in and out pins. This requires the devices on the SIO to be "smart", listening for commands being sent to their device number, decoding the instructions, and responding in kind. In previous Atari drives, this had been accomplished with the 6507, a cut-down version of the MOS 6502 that was being used in the Atari VCS console. The console ran at 1.1 MHz, but some 6507s supplied by Synertek failed to run at this speed reliably and were passed off to be used as SIO controllers running at lower speeds. For

3038-405: The same time, the videogame crash of 1983 was in full-swing. By the start of 1984, Atari was losing millions of dollars a day, and their owners, Warner Communications , became desperate to sell off the "loss-plagued" company. Atari was purchased by Jack Tramiel , formerly of Commodore, in June 1984. The new management arrived to find warehouses filled with XL systems and peripherals. They put

3100-424: The standard 128 byte "sectors", meaning that disks that were formatted with DOS 3 could not be read or written on other Atari machines unless they also updated to 3.0. The move to blocks meant that the minimum file size was also 1 kB, and in the era of small files this resulted in significant wasted space. This led most users to shun 3.0, and reviewers to state flatly that "This product should be avoided. It's

3162-410: The system transferred data at the original standard speed of 19,040 bps. This speed was much lower than the SIO was capable of, and had been selected simply because that was the limit of the logic analyzer available to the engineers designing the original 810s. The XF551, when operating in double-density mode, doubled this to 38,908 bps. SIO is a serial bus that sends commands and data over

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3224-619: The term "enhanced" or "dual density" to distinguish it from the true double-density systems already in the market. In contrast to the 810, which saw several upgrades during its time on the market, the 1050 saw only one major change. Production was first set up in Singapore in May 1983 and ran until December 1984, accounting for the majority of the production run. These units used the Tandon mechanism. In November 1984, production moved to Hong Kong , changing to

3286-460: The timing hole for both formatting and reading, and thus could not work with flippy disks at all. This limitation could be removed with the Enhancer. Because the drive mechanism was connected to the board using a standard connector, it was possible to replace it with a 3.5-inch mechanism, and this became quite popular. In contrast to the 810 and 1050, which ran at the non-standard speed of 288 RPM,

3348-403: Was a runaway success, prompting the Tramiels to reexamine the games console market. At the time, Atari had warehouses of the Atari 5200 and Atari 7800 which were put back on the market, but neither had been in production for some time and were built on pre-XE systems with no capability to produce more. This led to the decision to introduce a new console, the Atari XEGS , which was essentially

3410-441: Was acceptable and not overly restrictive. The entire 6500 CPU family was originally conceived as a line of very low-cost microprocessors for small-scale embedded systems. The 6507 and 6502 chips use the same underlying silicon layers, and differ only in the final metallisation layer. This ties the interrupt lines to their inactive level so they are not vulnerable to generating spurious interrupts from noise. The first three digits of

3472-519: Was aided by a MOS 6532 RIOT/PIA and a 6810 static RAM . The drive controller was the Western Digital WD2793 using MFM encoding for double-density support, although units built starting in the fall of 1985 used the WD2797. The drive ignored the alignment hole, and thus did not need the two-hole "flippy disk" to use the second side. It did respect the write-protect notch, so using the back side of

3534-401: Was doing well in the market and interest in the 8-bit platforms waned. An even further upgraded drive, the double-sided, double-density XF551 was being tested through this period, but the drive was not released. It was not until 1987, six months after 1050s had run out, that the XF551 finally shipped, and only after the threat of a lawsuit from Nintendo forced their hand. The 1050 moved to

3596-418: Was impossible to tell if it was being used without looking at the access LED. The only real complaints were the rear position of the power button, which made it difficult to access in some computer desks, and that it was very "fussy" about the diskettes, rejecting as many as 20% of low-cost floppies. In the end, it was "heartily recommend"ed, and "the best thing that's happened to Atari's 8-bit computer line since

3658-451: Was located directly below the LED, with a power indicator LED to its right. The back held the two drive number selection switches on the left, two SIO ports in the center, and the power ring jack on the right. The drive controller was a single card, unlike the two or three of the 810. It used a MOS 6507 as the SIO bus controller, running at 1 MHz rather than 500 kHz of the 810. The 6507

3720-459: Was marred by packaging it with an old version of Atari DOS which does not support the new features. This was addressed with DOS XE a year later. Support was dropped, along with the entire 8-bit computer line, in 1992. When the Atari 8-bit computers began shipping in 1979, Atari showed two floppy disk drive systems, the 810 and the 815. The 810 used the then-standard single-density FM encoding format that stored about 90 kB of data, while

3782-480: Was not a limitation of the bus itself. Third party drives normally used higher speeds, when run with suitable third-party DOSes, with some operating as high as the 52 kbps "Warp Speed" of the Happy 810 . For the new drive, Atari decided to double the rate to 38 kbps, although only when used with double-density disks. Atari DOS 2.5, introduced for the 1050 in 1983, did not support either capability. This had led to

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3844-585: Was the ICD Doubler, which added true double-density support allowing it to store 180 kB of data. This also added a high-speed mode that had been originally introduced in the Happy 810 modifications for the 810, increasing transfers from 19.2 kbps to 52 kbps. Happy also updated their original system for the 1050, becoming the Happy 1050, and like the Doubler it provided double-density support and its Warp Speed system. SpartaDOS , also from ICD, supported both

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