Talk:CompactFlash/Archive 1

Moving parts? Altitude limits?
Another difference between Compact Flash and Microdrive is that CF cards have --- I believe --- no moving parts. I've also heard that Microdrive does not work at high altitudes, due to insufficient air to float the disk head. Can anyone confirm these?

The Hitachi support site (with which company IBM has a partnership) quotes the operational altitude of Microdrives as -300 to 3000 meters, however I was unable to find confirmational specifications on the IBM site. Anecdotal evidence seems to support this (try Googling for Everest and Microdrive, for instance).

current records
What is the current record for (1) the largest capacity CF card (2) the fastest CF card (3) the smallest capacity CF card.


 * Can CF-I cards be used in CF-II slots?

You can use the CF I card in a CF II slot.

Chris Thames mavroxur@hotmail.com

AxelBoldt 21:27, 22 Nov 2004 (UTC)
 * Are the capacities in gigabytes or gibibytes?
 * Ok, I figured out the answers and put them into the article. AxelBoldt 23:52, 22 Nov 2004 (UTC)


 * I've seen CF cards as small as 4 megabytes, supplied as 'starter' cards with low-end HP digital cameras.

I & II
What the difference between type I and type II?

sorry, I am new, and don't know how to post a new question, so I just add my question in the answer part.

The difference between CF I and CFII is the physical thickness of the card. The electrical interface is the same (both in mechanical and signaling). CF I cards are 3.3mm thick, and CF II's are 5mm thick. For example, a CF I card will fit in a CF II slot, but not the other way around.

Chris Thames - mavroxur@hotmail.com

"Dominant Design question!"
As of late 2005. Do you think there's a dominant design in the flash memory market? Is there a dominant player (SanDisk, may be?) in the market? or the battle for the dominant design is still going on, and no single company has its design chosen as the dominant design yet?

'Enhanced' CF cards
Lexar produced (still does?) a line of 'USB Enabled' CompactFlash cards that are compatable with most standard CF devices. The concept with them was to include the USB controller on the CF card so that a less complex/expensive USB cable (called the jumpShot) could be used to read/write the cards with PC and Macintosh computers. These cards were initially produced in 1999~2000.

Unfortunately, some devices that are designed to only support strict adherence to the CF standard cannot use these Lexar cards. (One is the Handspring Visor line of PDAs with a Springboard to CF adaptor.)

un-delete CompactFlash drive ??
can anyone tell me if I can un-delete a Compactflash card to retrive files from it ?
 * This turns out to have nothing to do with compact flash. It depends on the filesystem on the drive (VFAT?) and the tools you have. DHR 21:12, 15 May 2006 (UTC)

Removed the word 'existing' from the phrase 'so the existing limitations of ATA were considered acceptable'. The word 'existing' in this context was redundant. Krymzn

CF Card operation and life expectancy?
The article should mention how a CF card actually stores data (at the bit level) and what the (expected) life-expectancy of a CF card should also be mentioned.

I was surprised at the lack of technical content in this article.

Jul. 23, 2006

This Needs a Rewrite
This whole entry needs a rewrite. It reads too much like an advertisement for SanDisk. The prose style needs work too.

There are ambiguities that need firming up -- "...about 8 megabytes to about 12 gigabytes...". Though I have found a company (Pretec) that lists a 12GB CompactFlash device (with solid-state memory, not a micro-drive). Also, several technical terms need links to their corresponding Wikipedia article, and some should be called by their IEEE name (as-in "FireWire" should at least mention IEEE-1394).

Can someone explain a use for a CompactFlash card that is not a storage device? Is there any item on the market that uses a CompactFlash card as Main Memory -- that is to say, computational space?

Charles Gaudette 17:05, 14 March 2006 (UTC)

There are lots of non-storage CF cards. See the article section "Other devices conforming to the CF standard". It seems unfortunate that this section appears to be an afterthought. I think the idea of supporting multiple types of devices should be very near the start. DHR 19:48, 21 March 2006 (UTC)

CF vs CF+ vs ATA
I'd like to know if certain disk drives will work in my PDA. The PDA has a CF II slot. This is supposed to support IDE (electircally). The disk drive is mechanically CF II but claims ATA (as opposed to CF) conformance. What does that mean? To me, ATA is a kind of IDE. There is a hint, but no explanation, in microdrive (last paragraph under "Applications"):

"Sometimes when a device with an integrated Microdrive stops working the device is taken apart and stripped of its Microdrive, which is then sold on. Unfortunately Microdrives taken from such devices may not work in digital cameras. The device must be accessed using ATA mode and therefore such drives do not fetch anywhere near as much as CF-enabled Microdrives as they cannot be used in devices that do not support ATA mode."

Is ATA mode part of CF+? DHR 19:48, 21 March 2006 (UTC)

Wear
The article points out CF appears similar to a hard drive. Should it point out that it doesn't support as many write cycles as a hard drive over its life?

jffs (Journaled Flash FilSystem) has a feature that spreads write cycles over the whole device (generally avoiding to rewrite the same block over itself); this grately reduces the chances of faliure on amy particula block of the flash device. Does the ATA interface embedded on CF devices make similar arrangements to reduce the possibility of faliure o a particular block being rewritten very often ?


 * Sooner or later, both media are vulnerable to occurrence of bad sectors(or blocks). Numbers of insertion/removal counts written in products specifications do mean that ratio of bad sectors is likely to increase when used beyond those numbers written, not that the products themselves become entirely useless at once.-ComSpex 08:54, 16 April 2006 (UTC)


 * See wear levelling DHR 04:22, 17 April 2006 (UTC)


 * Thank you, DHR. That's what I've looked around for.-ComSpex 08:09, 17 April 2006 (UTC)

64 GB announcement
I read that this article got bit and bytes mixed up. Might be worth looking into.


 * What do you mean? It means 64 gigabytes. The press release says:
 * "The 32Gb NAND flash memory can be used in memory cards with densities of up to 64-Gigabytes (GBs). One 64GB card can store over 64 hours of DVD resolution movies (40 movies) or 16,000 MP3 music files (1,340 hours)."
 * And please sign your comments. ---Majestic- 21:42, 5 October 2006 (UTC)


 * I removed the sentance "On September 11th, 2006 Samsung announced 32 GB and 64 GB CompactFlash card models[1]. These cards are based on a new technology that will make cards up to 256 GB possible." Read the release, samsung announced 64 gigabit NAND memory chips, no where did they mention compact flash cards (well, there was that picture of CF cards at the top of the page, which probably lead to the confusion).  These are higher capacity memory chips, which will likely make it into higher capacity CF cards eventually, increasing the maximum size.  Samsung doesn't even make CF cards any more AFK, they make the memory chips for them.  BTW I believe current 8gigabyte CF cards are based on 16gigabit chips.74.71.28.125 03:27, 9 November 2006 (UTC)

Price?
Can someone tell me the price for these CompactFlashes? like for a 128MB one to like a 10 GB one? To compare please? Josh215 14:40, 25 November 2006 (UTC)

Frame counters
The article currently has:

''With large-capacity cards, some cameras' frame counters may misbehave. For example, the Canon EOS 10D's frame counter displays "999" when a card has room for 1,000 or more photos remaining.''

This is the documented behaviour: the counter only has three digits so showing 999 means "999 or more." You can argue whether this is the best UI or not, but it's not a misbehaviour caused by large CF cards. So I might remove it. Subsolar 11:28, 2 May 2007 (UTC)

16 Bit Versus 32 Bit Buses
While this article does make it clear that there are two forms of CF cards more or less corresponding to the PCMCIA Type I and PCMCIA Type II cards, it is ambiguous about the bus organization of the cards. Is there a variation in bus specs for CF cards? Are some of them 16-bit and some of them 32-bit? I would guess that they all but universally support 32-bit 33 MHz CardBus these days, but my guesswork is too often wrong to be relied upon. Some clarification would be nice.

Also, the comment on "PCMCIA-ATA" seems confusing, all the more so because the WKPD article on PCMCIA doesn't mention ATA and the ATA article doesn't mention PCMCIA. Again, clarification might be nice.

MrG / (08 DEC 06) —The preceding unsigned comment was added by 4.228.21.104 (talk) 01:41, 9 December 2006 (UTC).


 * AFAIK, CF is a small formfactor PC Card, it's 16bit. PC Card is just the AT bus in a small card formfactor. IDE is just the 16bit AT bus extended off on a ribbon to your harddrive. So a CF device is an ISA expansion card in most respects. (An IDE/ATA harddrive is an ISA expansion card in many respects) controllers are onboard the CF card. 132.205.93.63 01:57, 13 June 2007 (UTC)

Unclear statement
''That is, it appears to the host device as if it were a hard disk of some defined size and has a tiny IDE controller onboard the CF device itself

Does a CompactFlash device appear to have an impossibly tiny IDE controller, or does it actually have an IDE controller which is unusually small? —Michael Z. 2007-01-05 02:36 Z 


 * AFAIK, CF is a small formfactor PC Card, it's 16bit. PC Card is just the AT bus in a small card formfactor. IDE is just the 16bit AT bus extended off on a ribbon to your harddrive. So a CF device is an ISA expansion card in most respects. (An IDE/ATA harddrive is an ISA expansion card in many respects) controllers are onboard the CF card. 132.205.93.63 01:57, 13 June 2007 (UTC)

relationship
It's rather unclear that CF is a development of PCMCIA in this article. Could someone rewrite it to indicate why CF type 1 and CF type 2 are exactly like PCMCIA type 1 and type 2, down to the electrical interface, and protocol? (or that PCMCIA itself is just the AT bus, IIRC) 132.205.93.63 02:00, 13 June 2007 (UTC)

Performance Citation
The main article needs a citation for performance. This site CF/SD Performance Database has performance benchmark on CF cards with Canon cameras. This site clearly shows that the smaller 2G card is faster then the 4G card as this article states. -dain 17:23, 30 July 2007 (UTC)

Other uses
Many of the latest generation of casino slot machines have their software on CompactFlash cards due to the security precautions of encasing the logic boards in full metal shields. The CF is accessed via a slot in the shielding. (Seen in a recent episode of "How it's Made".)

This came about due to a person who obtained a machine a few years ago and figured out a way to open the front without triggering the door open switch, then subverted the programming by holding a custom chip against the logic board via a curved piece of spring steel. Using a pair of accomplices to block security cameras, he was able to steal thousands of dollars.(Referenced from an episode of The History Channel series "Breaking Vegas".) —Preceding unsigned comment added by Bizzybody (talk • contribs) 08:40, 2 October 2007 (UTC)

Pin-out
It would be nice if the pin-out was added to the article. . . and how it compares to similar pin-outs, like for 1.8 HDDs. - Gus (T, C) 2007-07-03 17:04Z 17:04, 3 July 2007 (UTC)


 * while we're on pins, how about a photo of the "business end"? --Kvuo 23:37, 17 July 2007 (UTC)


 * I've added an external link pointing to a complete CompactFlash connector schematic and pinout. From the linked page is also possible to download the complete specifications. --Nicolaasuni (talk) 17:59, 15 April 2008 (UTC)

Links are messed up
so the link [11] is dead, but the link [12] seems to have the content that link #11 should have. but I am not sure because I dont know what link #11 contained before death..

--217.82.39.148 (talk) 13:55, 4 May 2008 (UTC)

Capacity
This section is inconsistent and out of date. —Preceding unsigned comment added by 217.35.91.11 (talk) 12:06, 15 August 2008 (UTC)

Hey, guys... I don't have the source with me to prove this at the moment... But I distinctly remember buying an 8 gig CF card in late 2001... It was just ridiculously expensive... If someone could find a source for me, that'd be great. —Preceding unsigned comment added by 146.151.49.74 (talk) 02:13, 30 January 2008 (UTC) Please take a look at www.memoryonlineshop.com/ebuy Memoryonlineshop (talk) 08:54, 1 August 2008 (UTC)

Filesystems section
The section on file systems needs to be rewritten, imo. The first two paragraphs are talking about cameras, even though the article is about CF cards. The last paragraph is the only one there that contains any relevant info about CF cards. —Preceding unsigned comment added by AnalogWeapon (talk • contribs) 15:38, 21 October 2008 (UTC)

Compatability
The page has a section of compatability, which doesn't really discuss compatability at all. There could also do with some details on what the size limit of each version of the standard is.

RandomCake (talk) 09:43, 13 November 2008 (UTC)

Grammar of Article
I found this article strange to read. The way it is written, and by whom, used "they" and "them" improper, in reference to objects and not beings. Unless CF Cards gain a soul and lifespan like a living being, these products can't be used in a "they" or "them" composition.

Coffee4binky (talk) 03:38, 25 November 2008 (UTC)

"CF device storage sizes are always a power of two"
Last statement in a capacity section states: "CF device storage sizes are always a power of two". But, as we can see from recent Pretec announce, there is at least one serious exception from this rule; if we can spell about 48GB as about raid of 32+16, for 100GB this should be 64GB+32GB+4GB, which seems ridiculously. Penartur (talk) 11:58, 25 September 2008 (UTC)
 * There are also Compact Flash cards from Mitsubishi with 22.5 MB. See http://img1.iwascoding.de/2/2008/11/11/BD84DF8233884051B27F25A75ADA588E.jpg – 91.4.2.111 (talk) 23:52, 20 December 2008 (UTC)

CF1 redirect
CF1 redirects here, with no mention of "CF1" in this article. What gives? 141.14.245.244 (talk) 10:53, 16 January 2009 (UTC)

PCMCIA and IDE
The article says "CompactFlash defines a physical interface which is smaller than, but electrically identical to, the ATA interface. That is, it appears to the host device as if it were a hard disk."

I was under the impression that the cards had two modes, one in which they acted like a PCMCIA flash card and one in which they acted like an IDE drive. Can anyone clarify? Plugwash (talk) 21:12, 19 January 2009 (UTC)

12 gigs?
"As of 2005, CompactFlash cards are available in capacities from about 8 megabytes to about 12 gigabytes." (Last sentence of description paragraph). I think the maximum number is around 4-6 gigs, or else Microdrives wouldn't exist :-)
 * While microdrives may have at one stage had higher maximum capacities than flash based CF cards that certainly isn't the case now and I don't think microdrives held the lead for very long either. The main area where microdrives led for ages (and possiblly still do) is in the cost per gigabyte. Plugwash (talk) 21:27, 19 January 2009 (UTC)

More (or better) info needed for usable device lifespan (related to write-cycle wear)
More could (or should) be said regarding the usable lifespan of these CF devices when they are used in consumer devices (mp3 players, cameras, etc) as well as their suitability as solid-state hard drives.

As well, are there any built-in logging or reporting mechanisms that can report the wear or dammage status of a CF module to the host (and ultimately to the user)?

Do software utilities exist that can report the degree that a given CF module is "worn out" or is close to (or has actually suffered from) non-operational data elements?

Can CF devices map worn-out memory elements as "bad sectors" such that they will no longer be used for data storage (just as hard drives do) ? —Preceding unsigned comment added by 70.50.52.95 (talk) 04:01, 7 February 2009 (UTC)

Class Descriptions
Several of the Compact Flash vendors currently use Class to describe the transfer rate? I am not 100% sure. For example there are Class 2 CF cards or Class 6 CF cards. Could we have a description that provides an explanation of the Class 'X' for CF cards. Mkrengas (talk) 17:46, 6 April 2009 (UTC)

Size standard confusion
I could go into the whole topic of the marketing lobby pushing an alteration of size standards in detail, but it is quite clear to the educated person anyway. Well, often for example MiB is used in the article, like "Samsung launched 16, 32 and 64 GiB CF cards soon after", neglecting that in the area of flash cards, that marketing trick of inflating numbers is used, too. For example, I've got a Lexar Professional CF 1 GB 80x, and its capacity (and that is also the drive, not only the partition, although that is actually nearly the same) is 1,031,372,800 Bytes, that is 983 'real' MB ... or MiB if you prefer. And here you see the fraud of it all: The change in standards has happened several years ago, and still the manufacturers don't use the 'i'-units. Or take a newer one: Sandisk Extreme III 8.0 GB: 8,193,507,328 Bytes. That is real 7.63 GB or GiB. Sandisk would have to label it something like "Sandisk Extreme III 8.1935 GiB" or "Sandisk Extreme III 7.63 GB". Some manufacturers (like Western Digital) say it like "GB MEANS this in this case, and that in that case.", but this goes against the whole purpose for having two separate standards (binary and decimal) in the first place. It's all a big lie and people who should know better follow like the herd they are, always obeying to new things without questioning them and examining what's going on. With flash cards there's also a specialty compared to harddisks: You noticed the 'excess capacity'? They change math in-between. Hard to describe. A "8 GB" flash card has (rounded) 8193 MB, and if you divide THIS (at the mega-level) by 1024, you get exactly 8 GB. But the point is that what you divided by 1024 there are no 8 GB, because they're 8193 million bytes, not real MB. It's actually a standard-change in-between. Totally crazy.

So I'm curious how this conflict will be solved in this and the many other Wikipedia articles. If you prefer to use the binary standard, you'd have to re-calculate every occurence of it in the articles. If you just change it all to the decimal standard, it is true to the label of the media and the actual capacity (in the case of harddisks, not flash memory), but further veils the truth behind it. And that's so funny: That so many people become so confused by it that they use it the wrong way; that they write "GiB" when there's no reason for not writing "GB". But this phenomenon is not unfamiliar to me. The same thing happened/happens in Germany when the written language was reformed a few years ago (in a crazy, illogical, doing-only-harm-no-good way). People were/are using the new rules where the old ones would still apply. This is not meant as an insult, but what can you expect from a society that celebrates the beginning of the new millennium at January 1st, 2000?! q.e.d.

SUPPLEMENT: I just noticed this article: http://en.wikipedia.org/wiki/Mebibyte There it is explained that mixing of standards had been done for a long time. Doesn't really surprise me. And I remember yeas ago when I was confused when a floppy disk was full, although I didn't copy more than 1,43 MB onto it. I thought it was due to the sector size, but turns out that their size is simply stated wrong. It had 1,38 or 1,39 MB. And this, too, has nothing to do with formatting.

Maybe someone should finally sue the industry for false advertising or consumer fraud or something like that for blatantly neglecting standards. --217.85.221.17 (talk) 22:28, 14 March 2010 (UTC)

Dell terminology, "CompactFlash Type II" confusion
This may be beyond the scope of the article. I was hoping to find exact term as used by Dell Axim owner's manual (x50 PDA), "CompactFlash Type II" and clear up my confussion do to various terminologies within the Industry. Could one discover the many terms as used by different manufacturers here in the article? I still am confused if these are simply synonyms: Seagate ST1 2.5GB Compact Flash MicroDrive CF II card, the Sony Compact Vault 5GB CF+ 1 inch Hard Disk Drive, the SanDisk ULTRA II CompactFlash CF 4GB and the Lexar 2GB CompactFlash Platinum II 80x, the SD SDHC Compact Flash Memory Card Adapter SLR, Sandisk Ultra II 4GB Compact Flash Cards and the list goes seemingly forever not once using Dell's terminolgy in their manual, Dell's manual quote, "Your device supports CompactFlash Type II cards." Apologies, the article is not clear, to me, if these are all the same or not CF cards. The article here is very goo in pointing out the current draw differences and physical descriptions and "pin-out" numbers (number of pins, not the schematic diagram of the pin's definition) of CF cards. This is a very good article. However, I was not able to "fish-out" of my confusion with all of the different Brand Names for Compact Flash Cards as if they may or may not be synonyms and cross compatable or not. I suppose it would be lengthy or cumbersome to have a paragragh of known synonyms usd in the the MFG industry of CF Cards. Otherwise, thank you WIKI editors for a very interesting article. Conaughy (talk) 08:00, 23 March 2010 (UTC)

Article too camera centric; added Reliability
Corrected Compactflash intro. The compactflash interface can be set as memory (up to 8 KiB), i/o, or IDE. It is used as an ATA disk not as memory. PCMCIA Memory Cards in cardbus mode were as fast as computer system video card bios and programs could be run at main memory speed. They had linear addressing to 32MiB, back in 2001 when Best Buy was selling 8 MiB CF for Canon cameras. Just as IDE was a 44-pin subset of the 98-pin ISA bus, so is the Compact flash 50-pin bus a subset of the PC Card 68-pin bus.

I have several embedded system board using Compact Flash cards as IDE hard drives. My iPAQ PDA has a CF 802.11 Wireless card. References from Sandisk which promulgated the standard have lost to the consumerism of their website; have they gone out of business yet? We can refer to the http://www.compactflash.org site but the "open" standard costs $100 to get. I've a copy of it from when I worked for Microsoft, and Samsung and Hitachi used to have copies on their websites.

My first brush with Compact Flash was in the 90s; it was used for IOS upgrades on Cisco i386 based routers after they took off the floppy. The only refs I can find are Linux blog entries. Cisco's website only wants to sell new stuff.

Added: ""===Reliability=== An important consideration for use in systems is Reliability. The original PC Card memory cards were battery backed ram then NOR flash. At the time NOR flash had a write endurance of 10,000 cycles (but no read liability). The currently used NAND flash has an endurance of 1,000,000 writes per location (less reliable than magnetic media) before hard failure and is prone to frequent soft errors on read. The CompactFlash card includes error checking and correction (ECC) and wear leveling circuitry that is transparent to the data user, although it may slow data access. The book "Car PC Hacks" suggest disabling Windows swap file and using EWF (Enhanced Write Filter) to eliminate unnecessary writes to CF storage media.""

Shjacks45 (talk) 11:07, 15 April 2010 (UTC)

Avoid long tables where a simple formula suffices
Please do not dumb down the article and do not consider readers incapable of multiplying two whole numbers, I would consider this insulting. In particular, I am talking about the speed rating table. How hard is it to multiply the rating number to 150 and then divide by 1000 to obtain speed in MBytes? Are readers THAT stupid that they cannot do second-grade math? Mikus (talk) 16:52, 11 May 2010 (UTC)

Power is not current
Consider (from the current version of the article):

"power draw can reach up to 350 milliamps and runs at 40-50 mA average power"

1. Something measured in mA is a current, not power.

2. However power may be more interesting than current. It could be computed and replace or supplement the two values for the current.

--Mortense (talk) 23:44, 12 May 2010 (UTC)
 * Correct. P = U * V, where V is usually 3.3 V, and sometimes 5 V for older cards or for Type II cards. Current is not power, one who wrote this would get F immediately at my school. Mikus (talk) 16:29, 13 May 2010 (UTC)

IDE "issues"
Section 2 of the article states, "CF cards may be set to master or slave, but have issues sharing the IDE bus." I have a dual CF-to-IDE adaptor that has "issues"--playing MP3 music from a CF is periodically interrupted when a second CF is present. Likewise, a Toshiba Satellite Pro 6100 doesn't play music smoothly from a CF in a PCMCIA adaptor. I am curious what the issues are and whether newer CF cards have resolved them. Can someone with expertise reply, or make the sentence in the article more specific? Spike-from-NH (talk) 16:07, 18 September 2011 (UTC)

Nikon "Flagship cameras" also use other card formats
The statement "Nikon use CompactFlash as storage medium for their flagship digital still cameras." is in danger of being misleading, because they also use other card formats. Nikon's D4 and D800 cameras use dual slots, one for CF and one other slot for SD in the D800 and XQD in the D4. In Nikon's consumer range recent cameras such as D600 and D7000 use dual SD slots. Reading between the lines, a recent Nikon survey of professional customers suggested that Nikon were weighing up a possible move to XQD. Canon recently introduced dual CF + SD slots in the EOS 5D, but retain dual CF in the EOS 1 cameras. In the end, provided performance is equal, the smaller formats will probably win.Plantsurfer (talk) 09:54, 23 October 2012 (UTC)


 * side issue - I have a Kingston 32GB 133X CF card that works fine in my Nikon D700 but is not even recognised by my new Nikon D800. Does anyone have any idea why?Plantsurfer (talk) 09:54, 23 October 2012 (UTC)

IEC prefixes should not be used here
...and not only because it's against WP:COMPUNITS (which it is, because our primary sources don't use them).

Although the flash memory chips inside CompactFlash devices no doubt come in sizes conveniently expressed as powers of 1024, that is not true of the CompactFlash cards they're packaged in, and it's the cards that are the subject of this artile. (Nor is it true of SecureDigital cards, nor USB flash "drives", nor SSDs in hard-drive-replacement form factors, nor mSATA cards... )

The solid-state "drive" industry follows the lead of the hard drive industry. "1 GB" on a CF card means 1,000,000,000 bytes, not 1024 cubed bytes. My references are below.

Accordingly, the notice in the "capacity" section here should be changed to read as follows:


 * Since flash memory products such as CompactFlash cards are produced and described in capacities that are small integer multiples of powers of 1000,   SI prefixes are used throughout this article. Thus a "64 GB" or "64 gigabyte" CompactFlash card is one with a capacity of 64,000,000,000 bytes (generally slightly more), not 64×10243 (which would be 68,719,476,736 bytes). Many operating systems will display such a "64 GB" device as providing about 59.6 GB capacity; this refers to 59.6×10243.

...and all uses of IEC prefixes should be changed to their SI counterparts.

The article currently claims, for example, that CF cards are available in "32 GiB" capacity. That would mean a capacity of 34,359,738,368 bytes. But a "32 GB" CF card does not provide that! It provides 32,000,000,000 bytes, or a little more. (I have one here. Windows shows it as 32,001,785,856 bytes, or "29.82 GB", and I assure you that the difference between this and 32 GiB is not due to formatting! Even if I wipe the partition structure completely, it still shows as 32 billion bytes.)

I know, I know. That's OR. But screen caps are acceptable in the Binary prefixes article. If necessary I'll provide them here.

The Binary prefixes article also contains, in the "legal disputes" section, confirmation of my claim. Vroegh v. Eastman Kodak happened because the flash memory card makers were using the SI prefix in its decimal meaning, and Vroegh expected them to be using binary, like the operating systems. And the manufacturers did NOT agree to change their labeling. Instead they all agreed to clarify their capacities on their packaging, stating e.g. "1 GB = one billion bytes", just the way the hard drive makers do.

To be numerically correct while using IEC prefixes this article would have to describe a "32 GB" CF card as a "29.8 GiB" card, and I hope we can all at least agree that that would be "not even wrong" (even though numerically correct!).

Please understand: I'm a proponent of the IEC binary prefixes. But they should not be used here, any more than they should be used in the Hard disk drive article. The CF makers are (with no exception that I can find) using SI prefixes with their SI interpretations, and furthermore are unambiguously documenting that usage (just as are the hard drive makers). So should this article. Jeh (talk) 08:25, 21 June 2014 (UTC)


 * I concur — a desire for orthodoxy seems to have raced past the real world being described. Spike-from-NH (talk) 13:05, 21 June 2014 (UTC)
 * I agree too. You pointed out [//en.wikipedia.org/w/index.php?title=CompactFlash&diff=294391689&oldid=294261454 my previous edit] on the subject. It's hard to remember since it was 5 years ago, but I don't think I thought through the issues of capacity labeling and error-correction at the time. —Moxfyre (ǝɹʎℲxoɯ &#124; contrib) 13:42, 21 June 2014 (UTC)
 * Ok, thanks for the replies! I'm going to wait another couple of days for input/suggestions/tweaks before changing anything.
 * btw, Moxfyre, it is indeed my understanding that allocation for ECC, wear-leveling, etc., is responsible for the difference between the "binary" capacity one might expect of a product containing a bunch of memory chips and the "decimal" capacities actually present at the connector. I would love to find an RS for that notion, but so far, nada. Jeh (talk) 17:59, 21 June 2014 (UTC)
 * Surely powers of two influence the CompactFlash architecture, such as the write and erase regions, also any wear-leveling and optimizations that depend on the design of FAT16/FAT32; just not the total memory capacity of the product. Spike-from-NH (talk) 03:13, 22 June 2014 (UTC)
 * Right - but all of the sizes mentioned here have to do with the latter, the total advertised capacity, as appears on the label. Anyway, hearing no objections... ✅. Please check my work for mistakes. Jeh (talk) 20:50, 27 June 2014 (UTC)

compact flash and memory card

 * Regarding my post to User talk:Ronkaufman:
 * And we have been edit-warring here on a related topic. Your assertion that CF was "the first memory card" (now you write "the first flash memory card") isn't true.  There were memory cards in the PC Card format before CF.  CF may have established "firsts," such as being a little more portable, but the one you claim is too categorical.  And a more precise explanation of what it was first at probably doesn't belong in the article's first sentence.  Spike-from-NH (talk) 14:33, 24 May 2015 (UTC)


 * PS--The previous guy's point is also relevant. If you are going to claim CF is the first at something, it's got to be more than you talking; you should give a citation that says so.  Spike-from-NH (talk) 14:35, 24 May 2015 (UTC)

the only memory card that came after the pc card is the compact flash no memory card beside the compact flash came after that. "The interface has spawned a generation of flash memory cards that set out to improve on the size and features of Type I cards: CompactFlash, MiniCard, P2 Card and SmartMedia. For example, the PC Card electrical specification is also used for CompactFlash, so a PC Card CompactFlash adapter need only be a socket adapter." https://en.wikipedia.org/wiki/PC_Card#Descendants_and_variants it is said the pc card was not flash memory card and gave birth to flash memory cards so it is make this the first flash memory card. — Preceding unsigned comment added by Ronkaufman (talk • contribs)

"and was the first flash memory card"
I removed this overly bold part. Naturally, it wasn't first mainly because CF interface is merely a subset of PCMCIA interface, which is predating CF for several years. Compact in Compact Flash stands for miniaturized PCMCIA. — Preceding unsigned comment added by 5.228.99.219 (talk • contribs)

the pcmcia was the first memory card but this is saying the first FLASH memory card not the first memory card huge different. — Preceding unsigned comment added by 213.57.164.29 (talk) 21:30, 11 August 2015 (UTC)


 * Wrong, I'm afraid. PCMCIA flash memory cards did exist and predated CompactFlash. Jeh (talk) 18:28, 9 November 2015 (UTC)


 * Designing with Flash Memory - The definitive guide to designing flash memory hardware and software for component and PCMCIA cards by Dipert and Levy. May 1, 1993. PCMCIA System Architecture by Don Anderson (Mindshare, Inc.) also has extensive information about flash memory PCMCIA cards. It is true that there were S-RAM memory cards in PCMCIA format, these being kept alive by an onboard battery like a coin cell. However PCMCIA flash cards definitely were made, for example by SanDisk. These did require considerably different software in the host - the Mindshare book describes both the S-RAM stack and the flash memory stack, along with the one for general purpose I/O interface. Jeh (talk) 11:28, 10 November 2015 (UTC)


 * 213.57.164.29 has been blocked as a sockpuppet. Nil Einne (talk) 14:13, 10 November 2015 (UTC)


 * Before being blocked the IP, apparently very eager to use as much as possible of the text he'd composed. ran off to PC card and claimed that that was the first memory card. I reverted that edit for this reason: The refs I gave above do not prove that PC card was the first memory card, only that it (under the name PCMCIA) did predate CompactFlash and that PCcard has been used for flash memory. In fact the Mindshare book does state (on page 14): "Numerous memory card manufacturers produced cards with differing physical and electrical properties... a standard physical package, electrical interface and connector were needed... several manufacturers met in the summer of 1988 to investigate ... a year later the Personal Computer Memory Card International Association was founded." i.e. there were memory cards that preceded PCMCIA. This doesn't say what the first flash memory card was; it may well have been PCMCIA (since the text just quoted does not specify "flash", only memory card). But we don't have a defnitive reference for that, so we can't say it. Jeh (talk) 09:49, 11 November 2015 (UTC)