Tom,
Here is some interesting history on the development of the double sided floppy drive.
I Googled for - shugart sa450 1976
Start reading around page 170
-- SWTPC6800 ( talk) 02:56, 13 April 2008 (UTC)
Hi, I wonder if you have a moment to give a third editor's opinion? I and editor Ramu50 are in a dispute on the AT Attachment page over whether solid state disks are supported under ATA. The issue is pretty well summarized in an [ [1]] I opened at reliable sources noticeboard. Ramu50 continues to remove the reference to solid state drives from the article lede, even though there is a citation supporting it. If you have a moment I'd appreciate your opinion, either in the form of assisting to revert what I consider vandalism to AT Attachment or comments on the talk page. (Sadly, admins have taken no action on my request to revert that page's recent rename.) Jeh ( talk) 07:35, 18 July 2008 (UTC)
It seems to me that the SA drives are Shugart Associates, and the ST are Seagate Technology. Was there an in-between time that was Shugart Technology?
Note that the ST506/ST412 manual in the references was published as Seagate Technology.
Gah4 ( talk) 01:36, 21 November 2008 (UTC)
See Early IBM disk storage#IBM 1311. Edward ( talk) 22:21, 31 December 2008 (UTC)
"With all due respect," I think you overstepped your mission in deleting almost all of the entry I edited last week declaring it "incorrect and too much information," and did so again when I rentered only my part of that entry (because I agreed the rest was TMI), but I challenge your statement that it was incorrect. In fact technically it is now incorrect, requiring a reader to view the footnote to get the true fact, which I'd say is an inconvenience at best. The fact is the company was founded as Shugart Technology and was no more than an office over a strip mall in Scotts Valley when I met there with Finis Conner in 1980 (construction for its building between the mall and the freeway broke ground shortly after I was there; I returned a few months later and saw the building complete, and by then the name was Seagate). If you think the TMI content preceding my first edit was incorrect, you should check it out before saying so - Al Shugart was an IBM employee before founding/co-founding SA and ST, and Finis, his cofounder at ST, was a former Memorex employee. If you had read the reference I inserted you would've known Al met Finis at Memorex in 1978. And any bio on Al says he left IBM in 1969. 01:33, 20 April 2010 (UTC) —Preceding unsigned comment added by 74.198.12.14 ( talk)
To sum up the above they worked together at Memorex prior to 1978 (when they met to discuss the subsequent founding of ST later that year) - they had attracted engineers from IBM to Memorex and hence to SA, thus the founders were ex-employees of both IBM and Memorex. Ergo, the entry deleted as "incorrect" was correct. 08:26, 20 April 2010 (UTC) —Preceding unsigned comment added by 74.198.12.14 ( talk)
You're playing that old "semantics game" simply for the sake of argument. (You assume that the original entry included the word "exclusively," which it didn't, to my recollection.) 01:42, 21 April 2010 (UTC) —Preceding unsigned comment added by 74.198.12.14 ( talk)
1979: Seagate Technology is founded by a group of ex-IBM and ex-Memorex personnel.
founder | last employer | next last | next last | next last |
---|---|---|---|---|
Shugart | unemployed | Shugart Assoc | Memorex | IBM |
Conner | IMI | Shugart Assoc | Memorex | |
Iftikar | Memorex | |||
Mahon | Shugart Assoc | Diablo | Xerox | |
Mitchell | Commodore | Bendix | Fairchild |
Thanks for the info - it seems to me you've proven the essential veracity of the TMI content with 60% of the founders (including both of the major players) meeting at least one of the dual criteria. I suspect the original author thought of the former colleagues of those 3, who brought their expertise from Memorex and IBM to SA and hence to ST, as part of the "groups," making it even more valid, despite the decade elapsed. (Remember that I have agreed that it was TMI for this section but it wasn't incorrect in that the word "exclusively" was not used - thus it becomes simply a matter of semantics.) 74.198.12.14 ( talk) 01:05, 26 April 2010 (UTC)
Buh? Why did you remove all the material on steppers and servos from the LLF article? None of that material is "specific to the IBM PC" as you commented at the time but was used by everyone in the industry across all manufacturers. The whole LLF section is basically devoid of content without those sections. As such I am in the process of reverting/restoring your content removal in July. DMahalko ( talk) 18:33, 26 November 2010 (UTC)
As well as I know it, 512 byte disk sectors were popular long before the IBM PC. The first computer system I remember them from is HP_Time-Shared_BASIC, but they were also popular on DEC systems like PDP-11 and VAX. The PDP-10 uses 576 byte sectors, or 128 of its 36 bit words, so a little more than 512. Seems to me that just about everyone except IBM's CKD used 512 or similar disk block sizes. Gah4 ( talk) 05:30, 14 September 2015 (UTC)
As for stepper motor, it does seem that was IBM. I remember a seek speed test program, run on an IBM (real) AT, and said something like "this drive is so slow, are you sure it isn't a floppy drive?" That was when I had a fast voice-coil Miniscribe 6053 at home. Gah4 ( talk) 22:35, 14 September 2015 (UTC)
I was not able to find any document suggesting Samsung had entered the worldwide HDD market in 1988. Would you be able to provide any reference? g2g886 ( talk) 08:04, 19 April 2011 (UTC)
I have some firsthand knowledge of the device having built them as a student intern in the early 80s on the assembly line. I took a rather tiny article and expanded it - it still could use some good fleshing out though. HP called it the BFD for at the tome they thought the capacity rather large. It was a staple on HP3000 & 9000 minicomputers. Not the most landmark device but was notable for a number of reasons. Mikebar ( talk) 01:06, 15 December 2011 (UTC)
Hi Tom, re my edits at floppy disk: The floppy disk drive indeed connects as a USB drive, as you said in your revert summary; but the article now says that the floppies themselves are used as an external drive, which doesn't make sense. Hence why I changed it to "could be used with an external USB drive", since you need the additional piece of hardware (USB FDD) to access floppies.
If you were thinking along the lines of "they are considered by the computer to be an external drive", in my experience USB floppy drives show up as drive A, so for all intents and purposes they are no different to an internal FDD. — This, that and the other (talk) 01:42, 20 November 2013 (UTC)
Hi Tom, I am looking for an explanation for the choice of a particular format filler value by various manufacturers and thought that you might know the answer.
For example, 8.0" (CP/M) floppy diskettes came pre-formatted with a filler value of E5h. (Since Tim Paterson took advantage of this fact, when he implemented the FAT12 file system for 86-DOS, this had and still has some interesting consequences for a number of odd implementation details of all FAT file systems up to the present.) But why were 8.0" floppies pre-formatted with E5h in the first place?
Another example: In all original IBM PCs since 1981 (and most compatible computers), freshly formatted floppies (and harddisks) are filled with a filler value of F6h. In IBM compatibles this value is stored in the Disk Parameter Table (INT 1Eh) by the BIOS and formatting tools (or formatting routines inside the BIOS) retrieve it from there during formatting. It can be changed easily to other values (and some clone manufacturers actually changed it to other values), but the question remains, why did IBM choose the value F6h, originally? What's special about it?
(Atari seems to have used E5h also on 5.25" and 3.5" floppies under GEM (probably by way of Digital Research), and Amstrad seems to have used F4h instead of F6h in some of their IBM PC compatible machines. On ROM and flash drives (which aren't actually formatted), the filler value often defaults to FFh in order to reduce wear, while on many modern hard disks it is 00h, if they are formatted by tools not adhering to INT 1Eh.)
Basically, these format filler values are "don't care" today, but I am trying to track down their origin and find out the technical reason for them. What I know for sure is that these values weren't a choice of random originally. I very vaguely remember having read somewhere (probably in the late 1980s or early 1990s), that this was down to FM/MFM properties or disk controller hardware peculiarities and seem to remember that these values represented bitpatterns particularly "good" to distinguish originally. But I am not sure about it any more and cannot remember the source.
Do you, perhaps, know the answer (or remember other format filler values by some vendors)?
Thanks and greetings -- Matthiaspaul ( talk) 13:28, 22 April 2014 (UTC)
I seem to remember that IBM had, for the s/360 line, a sort of a "core drive": A box with a MB or so of slow core in it, with a selector channel interface. It acted like a 1 MB very fast disk drive. Do you recall the model number? Jeh ( talk) 23:26, 22 July 2014 (UTC)
The Computing Barnstar
Tom94022 is hereby awarded this Computing Barnstar for DataVault and other outstanding contributions that have dramatically improved Wikipedia's coverage of how the bits are stored. – Margin1522 ( talk) 20:08, 17 January 2015 (UTC) |
Hi, could you point out which part of my statement is not true? Ufim ( talk) 14:11, 17 March 2019 (UTC)
Dear Tom,
Recently you mentioned there are more than 2 techniques for error correction.
Could you give me a clue? Perhaps the name of one of these other types of error correction? Perhaps a book or article that describes some other type of error correction? Is there maybe a Wikipedia article I've overlooked that mentions another type of error correction?
Clearly the error correction article *should* mention these other techniques for error correction, but currently the error correction article (in section error detection and correction#Types) claims there only 2 types of error correction: ARQ and FEC (and some systems use a hybrid of both types).
I look forward to learning something new. -- DavidCary ( talk) 14:25, 21 August 2019 (UTC)
If you are gonna remove all redlinks in List of computer hardware manufacturers, then be sure to remove those that appear in the cases section and in all sections as well. You seem to be removing only newly added redlinks. Pancho507 ( talk) 02:12, 22 September 2019 (UTC)
The article Cassette tape (obsolete) has been proposed for deletion because of the following concern:
Redundant to Cassette tape (disambiguation)
While all constructive contributions to Wikipedia are appreciated, pages may be deleted for any of several reasons.
You may prevent the proposed deletion by removing the {{proposed deletion/dated}}
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talk 02:32, 21 April 2020 (UTC)
A discussion is taking place as to whether the article Cassette tape (obsolete) is suitable for inclusion in Wikipedia according to Wikipedia's policies and guidelines or whether it should be deleted.
The article will be discussed at Wikipedia:Articles for deletion/Cassette tape (obsolete) until a consensus is reached, and anyone, including you, is welcome to contribute to the discussion. The nomination will explain the policies and guidelines which are of concern. The discussion focuses on high-quality evidence and our policies and guidelines.
Users may edit the article during the discussion, including to improve the article to address concerns raised in the discussion. However, do not remove the article-for-deletion notice from the top of the article. ... discospinster talk 16:13, 21 April 2020 (UTC)
There is an article: List_of_discontinued_photographic_films, and a variety of other such List of ... articles. I am not so sure about a List of discontinued cassette formats, but maybe List of discontinued audio recording systems, List of discontinued video recording systems, and 'List of discontinued data storage systems. Though I am not sure how many obsolete ones are actually discontinued. Gah4 ( talk) 17:00, 21 April 2020 (UTC)
This is a tangent to the WP:EL discussion, but "Carol" is a standard character in the story of Alice and Bob. See Alice and Bob#Cast of characters for a long list of names. WhatamIdoing ( talk) 03:27, 5 August 2020 (UTC)
[[Alice and Bob|Carol]]
, not to the disambiguation page. That link probably makes sense to most people who realized the names were in alphabetical order and who read the first sentence of the linked article ("fictional characters commonly used as a
placeholder name"). Anyone who wanted to be extra-certain that Carol belonged to that group needed only to finish reading the article.[[Carol]]
and it improperly got changed to what is now in one of the reversals of my changes. Regardless, I agree that most editors either never invoked the link or if they did and wound up at the disambiguation page did not care. That was my first response. And right now there are bigger issues in the article than this minor detail.
Tom94022 (
talk) 19:41, 7 August 2020 (UTC)
I'd like to clean up and complete the {{ cite}} templates in Mass storage and also quote the definition from the Naval Postgraduate School report; would you mind giving me a heads up when you're done with your current string of edits? Thanks. Shmuel (Seymour J.) Metz Username:Chatul ( talk) 23:25, 3 December 2020 (UTC)
This session explores mass storage systems with emphasis on design parameters, functional properties and their influence on applications. The class of device considered provides fast random-access to a large• capacity erasable store, available on-line to a data processor. Equipment with these properties satisfies the needs of users with business, scientific, and military applications.
The session opens with a survey paper defining the class of equipment to be discussed and then traces the historical development. Storage devices such as magnetic tape units and photographic equipment are not included since they do not satisfy the basic requirements. Next, the application requirements which led to particular design configurations are discussed. Individual characteristics of and comparisons between the following types of devices are examined: moving and fixed head drums and disc files; removable stack disc files; magnetic card memories and static mass memories. In addition, some predictions are made regarding the future dominance of moving media mass storage devices versus static mass memory storage devices.
The paper on the IBM 1311 Disc Storage Drive describes the improvement in technology required to achieve a system which features both high bit densities and the high degree of equipment compatibility needed to permit removable disc packs to be placed on other drive mechanisms and still maintain reliable operation. Design considerations involving a number of different technologies such as read/write heads, read/write electronics, air bearings and magnetic surfaces are covered in detail.
The paper on the Burroughs Disc File treats a different set of problems in the design of a storage device where access time depends only on rotational latency. In order to achieve large capacities in a fixed head file, high bit densities are used in conjunction with a multiplicity of heads. The disc itself is metallic coated, using electroplating techniques. The technology describes how several head assemblies are used in a single flying pad. In addition, the data organization, capacity and data rates are discussed. Finally the problem of switching between the heads and the packaging techniques are described.
The paper on the multiple-access disc file describes the Data Products dp/f-5035 DISCfiLE system. This is characterized by individual positioners for each disc and their utilization in a system configuration, where simultaneous data transfers may occur on two discs while two other positioners are also being moved to new locations at the same time. The design properties of the disc, heads and positioners are described, as well as the flexibility in operations obtained through the use of the individual positioners. The implication of the design on the performance of the associated data processor is also stressed.
The last paper deals with an approach by Thompson Ramo Wooldridge whereby a plated woven screen is used as the basic storage medium. Access to data is achieved by coincident-current switching. The method of storing with a woven aperture screen plane as well as the improvement in technology of plating to allow for the coincident-current mode will be discussed. The system has been investigated in a laboratory developmental program. The extension of techniques to a mass memory and the economics of the proposed design completes the paper.
In summary, three of the papers are devoted to newly announced equipment configurations utilizing rotating discs for storage, but each having a different design goal and hence utility in different application areas. The fourth paper covers an all solid state approach which has an access time approaching that of core memories but a higher cost-per-bit and is not yet available. The survey paper serves to show relationships, advantages and disadvantages to the various approaches. The session will also stress the relationship between economic factors and performance.
Datamation, October 1963, p. 53-4
@ Chatul: it looks pretty good, maybe I'll add something from 1963 FJCC thereby pushing the date back even further and establishing the term was originally applied to secondary storage devices like HDDs. Now we should clean up media section which is a non-sequitur at best. Tom94022 ( talk) 02:01, 5 December 2020 (UTC)
Notes
Deleted
Hey there! I want to thank you for correcting errors in the Computer data storage article. I've noticed you've changed some "GiB" to "GB" on your edit here. I just want to let you know that the "GiB" are not typos. The "GiB" stands for gibibytes (which are different from gigabytes). You may already know the difference between "GiB" and "GB", but I'll just briefly explain for your convenience, because this misunderstanding is quite common in the industry. A GiB is equivalent to exactly 1073741824 bytes (1024^3), whereas a gigabyte has exactly 1000000000 bytes (1000^3). Usually, if you see numbers that are powers of 2 (numbers such as 16, 32, 64, etc. especially for things like RAM) it usually uses binary prefixes of KiB, MiB, and GiB, etc. Let me know if that clarifies any confusion. Somerandomuser ( talk) 22:07, 3 February 2022 (UTC)
@ Somerandomuser: Perhaps you are not aware that IEC Binary prefixes are not allowed in this Wikipedia except in limited situations - for the most part we editors are required to use the so-called conventional binary prefixes such as GB instead of GiB. Personally I think it is a mistake to deprecate the IEC binary prefixes. Let me know if that clarifies any confusion you may have. I invite you to start a dialog at Wikipedia:Manual of Style/Dates and numbers to allow broader usage of these prefixes. Tom94022 ( talk) 07:46, 4 February 2022 (UTC)
Hi,
As I have previously stated in the edits, the correct category is Category:Instruction set architectures and not Category:Computer architecture for two reasons:
1. The article primarily deals with the ISA from my limited understanding. In that perspective, categories should relate directly to the article, otherwise we would have multiple unrelated and sometimes conflicting categories.
2. Category:Instruction set architectures is a subcategory of Category:Computer architecture, therefore having the latter category separately mentioned is redundant, especially given that it is a diffusing category.
Let me know your thoughts.
Best regards, CoolingGibbon ( talk) 15:22, 2 January 2023 (UTC)
EDIT: However, I would be in favor of having the article in either of the two categories, depending on whatever is suitable, but not both simultaneously.
Where are floppies still in use? And at what point does the usage fall below the threshold from largely obsolete to obsolete? Mtpaley ( talk) 22:54, 18 April 2023 (UTC)
You are misstating wikipedia policy. /info/en/?search=Wikipedia:Reliable_source_examples states that "They are reliable as a citation to the existence of an invention and its date (e.g., "A patent was issued to Alice Expert on May 5, 2010..."). They are reliable for attributed statements about their contents (e.g., "According to five-year-old inventor Steven Olson in his application for US Patent #6,368,227, issued in 2002, he invented swinging sideways because swinging back and forth might get boring.") A patent will also contain a section referencing previous literature, which may be a good source to search for other citations." As such, the patent cited supports the edits I made and unless you provide contrary evidence , I ask that you restore my edits. Bangthedash101 ( talk) 20:52, 21 February 2024 (UTC)
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Tom,
Here is some interesting history on the development of the double sided floppy drive.
I Googled for - shugart sa450 1976
Start reading around page 170
-- SWTPC6800 ( talk) 02:56, 13 April 2008 (UTC)
Hi, I wonder if you have a moment to give a third editor's opinion? I and editor Ramu50 are in a dispute on the AT Attachment page over whether solid state disks are supported under ATA. The issue is pretty well summarized in an [ [1]] I opened at reliable sources noticeboard. Ramu50 continues to remove the reference to solid state drives from the article lede, even though there is a citation supporting it. If you have a moment I'd appreciate your opinion, either in the form of assisting to revert what I consider vandalism to AT Attachment or comments on the talk page. (Sadly, admins have taken no action on my request to revert that page's recent rename.) Jeh ( talk) 07:35, 18 July 2008 (UTC)
It seems to me that the SA drives are Shugart Associates, and the ST are Seagate Technology. Was there an in-between time that was Shugart Technology?
Note that the ST506/ST412 manual in the references was published as Seagate Technology.
Gah4 ( talk) 01:36, 21 November 2008 (UTC)
See Early IBM disk storage#IBM 1311. Edward ( talk) 22:21, 31 December 2008 (UTC)
"With all due respect," I think you overstepped your mission in deleting almost all of the entry I edited last week declaring it "incorrect and too much information," and did so again when I rentered only my part of that entry (because I agreed the rest was TMI), but I challenge your statement that it was incorrect. In fact technically it is now incorrect, requiring a reader to view the footnote to get the true fact, which I'd say is an inconvenience at best. The fact is the company was founded as Shugart Technology and was no more than an office over a strip mall in Scotts Valley when I met there with Finis Conner in 1980 (construction for its building between the mall and the freeway broke ground shortly after I was there; I returned a few months later and saw the building complete, and by then the name was Seagate). If you think the TMI content preceding my first edit was incorrect, you should check it out before saying so - Al Shugart was an IBM employee before founding/co-founding SA and ST, and Finis, his cofounder at ST, was a former Memorex employee. If you had read the reference I inserted you would've known Al met Finis at Memorex in 1978. And any bio on Al says he left IBM in 1969. 01:33, 20 April 2010 (UTC) —Preceding unsigned comment added by 74.198.12.14 ( talk)
To sum up the above they worked together at Memorex prior to 1978 (when they met to discuss the subsequent founding of ST later that year) - they had attracted engineers from IBM to Memorex and hence to SA, thus the founders were ex-employees of both IBM and Memorex. Ergo, the entry deleted as "incorrect" was correct. 08:26, 20 April 2010 (UTC) —Preceding unsigned comment added by 74.198.12.14 ( talk)
You're playing that old "semantics game" simply for the sake of argument. (You assume that the original entry included the word "exclusively," which it didn't, to my recollection.) 01:42, 21 April 2010 (UTC) —Preceding unsigned comment added by 74.198.12.14 ( talk)
1979: Seagate Technology is founded by a group of ex-IBM and ex-Memorex personnel.
founder | last employer | next last | next last | next last |
---|---|---|---|---|
Shugart | unemployed | Shugart Assoc | Memorex | IBM |
Conner | IMI | Shugart Assoc | Memorex | |
Iftikar | Memorex | |||
Mahon | Shugart Assoc | Diablo | Xerox | |
Mitchell | Commodore | Bendix | Fairchild |
Thanks for the info - it seems to me you've proven the essential veracity of the TMI content with 60% of the founders (including both of the major players) meeting at least one of the dual criteria. I suspect the original author thought of the former colleagues of those 3, who brought their expertise from Memorex and IBM to SA and hence to ST, as part of the "groups," making it even more valid, despite the decade elapsed. (Remember that I have agreed that it was TMI for this section but it wasn't incorrect in that the word "exclusively" was not used - thus it becomes simply a matter of semantics.) 74.198.12.14 ( talk) 01:05, 26 April 2010 (UTC)
Buh? Why did you remove all the material on steppers and servos from the LLF article? None of that material is "specific to the IBM PC" as you commented at the time but was used by everyone in the industry across all manufacturers. The whole LLF section is basically devoid of content without those sections. As such I am in the process of reverting/restoring your content removal in July. DMahalko ( talk) 18:33, 26 November 2010 (UTC)
As well as I know it, 512 byte disk sectors were popular long before the IBM PC. The first computer system I remember them from is HP_Time-Shared_BASIC, but they were also popular on DEC systems like PDP-11 and VAX. The PDP-10 uses 576 byte sectors, or 128 of its 36 bit words, so a little more than 512. Seems to me that just about everyone except IBM's CKD used 512 or similar disk block sizes. Gah4 ( talk) 05:30, 14 September 2015 (UTC)
As for stepper motor, it does seem that was IBM. I remember a seek speed test program, run on an IBM (real) AT, and said something like "this drive is so slow, are you sure it isn't a floppy drive?" That was when I had a fast voice-coil Miniscribe 6053 at home. Gah4 ( talk) 22:35, 14 September 2015 (UTC)
I was not able to find any document suggesting Samsung had entered the worldwide HDD market in 1988. Would you be able to provide any reference? g2g886 ( talk) 08:04, 19 April 2011 (UTC)
I have some firsthand knowledge of the device having built them as a student intern in the early 80s on the assembly line. I took a rather tiny article and expanded it - it still could use some good fleshing out though. HP called it the BFD for at the tome they thought the capacity rather large. It was a staple on HP3000 & 9000 minicomputers. Not the most landmark device but was notable for a number of reasons. Mikebar ( talk) 01:06, 15 December 2011 (UTC)
Hi Tom, re my edits at floppy disk: The floppy disk drive indeed connects as a USB drive, as you said in your revert summary; but the article now says that the floppies themselves are used as an external drive, which doesn't make sense. Hence why I changed it to "could be used with an external USB drive", since you need the additional piece of hardware (USB FDD) to access floppies.
If you were thinking along the lines of "they are considered by the computer to be an external drive", in my experience USB floppy drives show up as drive A, so for all intents and purposes they are no different to an internal FDD. — This, that and the other (talk) 01:42, 20 November 2013 (UTC)
Hi Tom, I am looking for an explanation for the choice of a particular format filler value by various manufacturers and thought that you might know the answer.
For example, 8.0" (CP/M) floppy diskettes came pre-formatted with a filler value of E5h. (Since Tim Paterson took advantage of this fact, when he implemented the FAT12 file system for 86-DOS, this had and still has some interesting consequences for a number of odd implementation details of all FAT file systems up to the present.) But why were 8.0" floppies pre-formatted with E5h in the first place?
Another example: In all original IBM PCs since 1981 (and most compatible computers), freshly formatted floppies (and harddisks) are filled with a filler value of F6h. In IBM compatibles this value is stored in the Disk Parameter Table (INT 1Eh) by the BIOS and formatting tools (or formatting routines inside the BIOS) retrieve it from there during formatting. It can be changed easily to other values (and some clone manufacturers actually changed it to other values), but the question remains, why did IBM choose the value F6h, originally? What's special about it?
(Atari seems to have used E5h also on 5.25" and 3.5" floppies under GEM (probably by way of Digital Research), and Amstrad seems to have used F4h instead of F6h in some of their IBM PC compatible machines. On ROM and flash drives (which aren't actually formatted), the filler value often defaults to FFh in order to reduce wear, while on many modern hard disks it is 00h, if they are formatted by tools not adhering to INT 1Eh.)
Basically, these format filler values are "don't care" today, but I am trying to track down their origin and find out the technical reason for them. What I know for sure is that these values weren't a choice of random originally. I very vaguely remember having read somewhere (probably in the late 1980s or early 1990s), that this was down to FM/MFM properties or disk controller hardware peculiarities and seem to remember that these values represented bitpatterns particularly "good" to distinguish originally. But I am not sure about it any more and cannot remember the source.
Do you, perhaps, know the answer (or remember other format filler values by some vendors)?
Thanks and greetings -- Matthiaspaul ( talk) 13:28, 22 April 2014 (UTC)
I seem to remember that IBM had, for the s/360 line, a sort of a "core drive": A box with a MB or so of slow core in it, with a selector channel interface. It acted like a 1 MB very fast disk drive. Do you recall the model number? Jeh ( talk) 23:26, 22 July 2014 (UTC)
The Computing Barnstar
Tom94022 is hereby awarded this Computing Barnstar for DataVault and other outstanding contributions that have dramatically improved Wikipedia's coverage of how the bits are stored. – Margin1522 ( talk) 20:08, 17 January 2015 (UTC) |
Hi, could you point out which part of my statement is not true? Ufim ( talk) 14:11, 17 March 2019 (UTC)
Dear Tom,
Recently you mentioned there are more than 2 techniques for error correction.
Could you give me a clue? Perhaps the name of one of these other types of error correction? Perhaps a book or article that describes some other type of error correction? Is there maybe a Wikipedia article I've overlooked that mentions another type of error correction?
Clearly the error correction article *should* mention these other techniques for error correction, but currently the error correction article (in section error detection and correction#Types) claims there only 2 types of error correction: ARQ and FEC (and some systems use a hybrid of both types).
I look forward to learning something new. -- DavidCary ( talk) 14:25, 21 August 2019 (UTC)
If you are gonna remove all redlinks in List of computer hardware manufacturers, then be sure to remove those that appear in the cases section and in all sections as well. You seem to be removing only newly added redlinks. Pancho507 ( talk) 02:12, 22 September 2019 (UTC)
The article Cassette tape (obsolete) has been proposed for deletion because of the following concern:
Redundant to Cassette tape (disambiguation)
While all constructive contributions to Wikipedia are appreciated, pages may be deleted for any of several reasons.
You may prevent the proposed deletion by removing the {{proposed deletion/dated}}
notice, but please explain why in your
edit summary or on
the article's talk page.
Please consider improving the page to address the issues raised. Removing {{proposed deletion/dated}}
will stop the
proposed deletion process, but other
deletion processes exist. In particular, the
speedy deletion process can result in deletion without discussion, and
articles for deletion allows discussion to reach
consensus for deletion. ...
discospinster
talk 02:32, 21 April 2020 (UTC)
A discussion is taking place as to whether the article Cassette tape (obsolete) is suitable for inclusion in Wikipedia according to Wikipedia's policies and guidelines or whether it should be deleted.
The article will be discussed at Wikipedia:Articles for deletion/Cassette tape (obsolete) until a consensus is reached, and anyone, including you, is welcome to contribute to the discussion. The nomination will explain the policies and guidelines which are of concern. The discussion focuses on high-quality evidence and our policies and guidelines.
Users may edit the article during the discussion, including to improve the article to address concerns raised in the discussion. However, do not remove the article-for-deletion notice from the top of the article. ... discospinster talk 16:13, 21 April 2020 (UTC)
There is an article: List_of_discontinued_photographic_films, and a variety of other such List of ... articles. I am not so sure about a List of discontinued cassette formats, but maybe List of discontinued audio recording systems, List of discontinued video recording systems, and 'List of discontinued data storage systems. Though I am not sure how many obsolete ones are actually discontinued. Gah4 ( talk) 17:00, 21 April 2020 (UTC)
This is a tangent to the WP:EL discussion, but "Carol" is a standard character in the story of Alice and Bob. See Alice and Bob#Cast of characters for a long list of names. WhatamIdoing ( talk) 03:27, 5 August 2020 (UTC)
[[Alice and Bob|Carol]]
, not to the disambiguation page. That link probably makes sense to most people who realized the names were in alphabetical order and who read the first sentence of the linked article ("fictional characters commonly used as a
placeholder name"). Anyone who wanted to be extra-certain that Carol belonged to that group needed only to finish reading the article.[[Carol]]
and it improperly got changed to what is now in one of the reversals of my changes. Regardless, I agree that most editors either never invoked the link or if they did and wound up at the disambiguation page did not care. That was my first response. And right now there are bigger issues in the article than this minor detail.
Tom94022 (
talk) 19:41, 7 August 2020 (UTC)
I'd like to clean up and complete the {{ cite}} templates in Mass storage and also quote the definition from the Naval Postgraduate School report; would you mind giving me a heads up when you're done with your current string of edits? Thanks. Shmuel (Seymour J.) Metz Username:Chatul ( talk) 23:25, 3 December 2020 (UTC)
This session explores mass storage systems with emphasis on design parameters, functional properties and their influence on applications. The class of device considered provides fast random-access to a large• capacity erasable store, available on-line to a data processor. Equipment with these properties satisfies the needs of users with business, scientific, and military applications.
The session opens with a survey paper defining the class of equipment to be discussed and then traces the historical development. Storage devices such as magnetic tape units and photographic equipment are not included since they do not satisfy the basic requirements. Next, the application requirements which led to particular design configurations are discussed. Individual characteristics of and comparisons between the following types of devices are examined: moving and fixed head drums and disc files; removable stack disc files; magnetic card memories and static mass memories. In addition, some predictions are made regarding the future dominance of moving media mass storage devices versus static mass memory storage devices.
The paper on the IBM 1311 Disc Storage Drive describes the improvement in technology required to achieve a system which features both high bit densities and the high degree of equipment compatibility needed to permit removable disc packs to be placed on other drive mechanisms and still maintain reliable operation. Design considerations involving a number of different technologies such as read/write heads, read/write electronics, air bearings and magnetic surfaces are covered in detail.
The paper on the Burroughs Disc File treats a different set of problems in the design of a storage device where access time depends only on rotational latency. In order to achieve large capacities in a fixed head file, high bit densities are used in conjunction with a multiplicity of heads. The disc itself is metallic coated, using electroplating techniques. The technology describes how several head assemblies are used in a single flying pad. In addition, the data organization, capacity and data rates are discussed. Finally the problem of switching between the heads and the packaging techniques are described.
The paper on the multiple-access disc file describes the Data Products dp/f-5035 DISCfiLE system. This is characterized by individual positioners for each disc and their utilization in a system configuration, where simultaneous data transfers may occur on two discs while two other positioners are also being moved to new locations at the same time. The design properties of the disc, heads and positioners are described, as well as the flexibility in operations obtained through the use of the individual positioners. The implication of the design on the performance of the associated data processor is also stressed.
The last paper deals with an approach by Thompson Ramo Wooldridge whereby a plated woven screen is used as the basic storage medium. Access to data is achieved by coincident-current switching. The method of storing with a woven aperture screen plane as well as the improvement in technology of plating to allow for the coincident-current mode will be discussed. The system has been investigated in a laboratory developmental program. The extension of techniques to a mass memory and the economics of the proposed design completes the paper.
In summary, three of the papers are devoted to newly announced equipment configurations utilizing rotating discs for storage, but each having a different design goal and hence utility in different application areas. The fourth paper covers an all solid state approach which has an access time approaching that of core memories but a higher cost-per-bit and is not yet available. The survey paper serves to show relationships, advantages and disadvantages to the various approaches. The session will also stress the relationship between economic factors and performance.
Datamation, October 1963, p. 53-4
@ Chatul: it looks pretty good, maybe I'll add something from 1963 FJCC thereby pushing the date back even further and establishing the term was originally applied to secondary storage devices like HDDs. Now we should clean up media section which is a non-sequitur at best. Tom94022 ( talk) 02:01, 5 December 2020 (UTC)
Notes
Deleted
Hey there! I want to thank you for correcting errors in the Computer data storage article. I've noticed you've changed some "GiB" to "GB" on your edit here. I just want to let you know that the "GiB" are not typos. The "GiB" stands for gibibytes (which are different from gigabytes). You may already know the difference between "GiB" and "GB", but I'll just briefly explain for your convenience, because this misunderstanding is quite common in the industry. A GiB is equivalent to exactly 1073741824 bytes (1024^3), whereas a gigabyte has exactly 1000000000 bytes (1000^3). Usually, if you see numbers that are powers of 2 (numbers such as 16, 32, 64, etc. especially for things like RAM) it usually uses binary prefixes of KiB, MiB, and GiB, etc. Let me know if that clarifies any confusion. Somerandomuser ( talk) 22:07, 3 February 2022 (UTC)
@ Somerandomuser: Perhaps you are not aware that IEC Binary prefixes are not allowed in this Wikipedia except in limited situations - for the most part we editors are required to use the so-called conventional binary prefixes such as GB instead of GiB. Personally I think it is a mistake to deprecate the IEC binary prefixes. Let me know if that clarifies any confusion you may have. I invite you to start a dialog at Wikipedia:Manual of Style/Dates and numbers to allow broader usage of these prefixes. Tom94022 ( talk) 07:46, 4 February 2022 (UTC)
Hi,
As I have previously stated in the edits, the correct category is Category:Instruction set architectures and not Category:Computer architecture for two reasons:
1. The article primarily deals with the ISA from my limited understanding. In that perspective, categories should relate directly to the article, otherwise we would have multiple unrelated and sometimes conflicting categories.
2. Category:Instruction set architectures is a subcategory of Category:Computer architecture, therefore having the latter category separately mentioned is redundant, especially given that it is a diffusing category.
Let me know your thoughts.
Best regards, CoolingGibbon ( talk) 15:22, 2 January 2023 (UTC)
EDIT: However, I would be in favor of having the article in either of the two categories, depending on whatever is suitable, but not both simultaneously.
Where are floppies still in use? And at what point does the usage fall below the threshold from largely obsolete to obsolete? Mtpaley ( talk) 22:54, 18 April 2023 (UTC)
You are misstating wikipedia policy. /info/en/?search=Wikipedia:Reliable_source_examples states that "They are reliable as a citation to the existence of an invention and its date (e.g., "A patent was issued to Alice Expert on May 5, 2010..."). They are reliable for attributed statements about their contents (e.g., "According to five-year-old inventor Steven Olson in his application for US Patent #6,368,227, issued in 2002, he invented swinging sideways because swinging back and forth might get boring.") A patent will also contain a section referencing previous literature, which may be a good source to search for other citations." As such, the patent cited supports the edits I made and unless you provide contrary evidence , I ask that you restore my edits. Bangthedash101 ( talk) 20:52, 21 February 2024 (UTC)
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