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Yes, it really is true -- at least on some older motherboards, unplugging a PS/2 device while powered will occasionally at least semi-permanently break the motherboard, such as blowing a special fuse. - 69.87.204.161 01:03, 19 March 2007 (UTC)
I corrected some spelling errors. jpoke89 ( talk) 11:49, 22 November 2007 (UTC)
Care should be taken to avoid connecting a keyboard to a mouse port or vice versa.[citation needed]
That's BS. Electrically they're the same. They signal the same. On all modern motherboards both ports even go to the same chip. The data format is different, but you won't harm or break anything by plugging the wrong thing into the wrong port. —Preceding unsigned comment added by 72.29.167.236 ( talk) 19:22, 20 September 2008 (UTC)
Interestingly the 1st reference on this subject appears to be a comment, rather than a reference... PrimalBlueWolf ( talk) 10:59, 25 March 2020 (UTC)
What was the connector used in the original IBM PC? Family Guy Guy ( talk) 04:34, 19 November 2008 (UTC)
The article should contain a section in which the compatibility of PS/2-to-USB and vice versa is discuessed. Simple adapters exist both for plugging PS/2-hardware into USB sockets, as well as for plugging USB-hardware into PS/2 sockets. -- Alexey Topol ( talk) 16:31, 27 March 2010 (UTC)
Really? I've not bought a retail PC for years but almost no mobo's for self build had PS/2 ports when I was self building in '08. Anyone else think this is a bit out dated and that now almost all KB and mouse are usb as well as PS/2 being largely dropped from new pc's? —Preceding unsigned comment added by 77.197.60.204 ( talk) 12:38, 25 August 2010 (UTC)
T O T A L |
PS/2 | |||
---|---|---|---|---|
# W I T H O U T |
% W I T H | |||
AMD | 148 | 3 | 98 | 95 |
Intel | 317 | 23 | 93 |
I went through every AMD and Intel mobo listing at newegg.com the other day before I removed the (unreferenced) blurb about PS/2 ports "frequently" not being included (results at left).
I didn't bother with the "Motherboard / CPU / VGA Combo" and "Server Motherboards" categories, but 100% of the "Top Sellers" in them have PS/2 ports.
As for retail PCs, I bought a compact tower
Acer from BestBuy last year that has seven USB ports and individual PS/2 ports for keyboard and mouse (as well as many other ports). ¦
Reisio (
talk) 23:29, 7 January 2011 (UTC)
Consensus is determined by the quality of the arguments given on the various sides of an issue, as viewed through the lens of Wikipedia policy.
Wikipedia is not an experiment in democracy or any other political system. Its primary (though not exclusive) means of decision making and conflict resolution is editing and discussion leading to consensus—not voting.
Consensus among a limited group of editors, at one place and time, cannot override community consensus on a wider scale. For instance, unless they can convince the broader community that such action is right, participants in a WikiProject cannot decide that some generally accepted policy or guideline does not apply to articles within its scope.
Would you accept a wording change to something like "PS/2 connectors are still present on some current PCs and component motherboards"? I believe that that claim is sufficiently noncontroversial that a citation is not needed. I would also ask that you not delete my add regarding availability of new PS/2 compatible mice and keyboards. No, it is not proven, but that is what a CN tag is for. Jeh ( talk) 02:21, 6 February 2013 (UTC)
But there is a citable source for "some", whereas there is none for "most". Jeh ( talk) 21:54, 7 February 2013 (UTC)
CN means "it may be that this claim is true, but no reliable, published sources were given to verify it and the information is not considered common knowledge". That is a direct quote from the template description. It goes on to say that the template should be used "when there is a general question of the verifiability of a statement, or when an editor believes that a reference verifying the statement should be provided."
This is why I insist on a CN tag for your "most." You see, the CN tag does not mean "I claim it's not true." It does not even mean "I'm doubtful about this." (There is a "doubtful" tag for that.) I'm saying it's not self-evident the way "the sky is blue" is, nor common knowledge like "the moon orbits the Earth" is, so by WP:V it needs to be cited. And the survey you did two years ago, while providing sufficient motivation for the inclusion of the claim, is not something that we can use as a citation nor sufficient to remove the CN tag.
If I thought the "most motherboards" claim wasn't true I'd have used a "doubtful" tag instead. That validity of the claim is not what this dispute is about. The fact that it lacks a citation is. Jeh ( talk) 08:36, 6 February 2013 (UTC)
No, I'm not ignoring you. I'm trying to get you to see that you can't simply ignore WP policy. The "self-evidentiary" nature of your claim is not what is under discussion. What is relevant to inclusion on Wikipedia is whether it is verifiable.
I'm afraid that words like "reliable source", "published", and "verifiable" do indeed have specific meanings in the context of WP policy. And regardless of how they are used elsewhere, when writing for WP and defending your work here, you must use WP's meanings. Otherwise your position here may be indefensible.
In particular, you write "The validity is the only thing that matters." I tell you three times: WP policy disagrees with you. WP:V states that all material added to WP must be verifiable, according to WP's definition of "verifiable", from what WP considers "reliable, published sources." Otherwise it can't be here, no matter how true it is, no matter how true you "know" it is, no matter how satisfied you are from your own research. That's WP:V in a nutshell. And there is no provision I can find that would allow any other policy to override that.
I really think you need to read all of WP:V, and as well, the essay "verifiability, not truth") for some of the rationale behind it.
And then you need not to say "but, I can ignore all that, because I know this claim is true."
Similarly the criteria for "reliable" generally excludes self-published sources (like online catalogs); see WP:RS.
However! I think I found an "out". WP:RS does allow that "Self-published or questionable sources may be used as sources of information about themselves" (emph. added). So a statement along the lines of "At least one PS/2 port can be found on most of the component motherboards offered by one on-line vendor", with a link to Newegg's "motherboards" listings, seems to me to be acceptable. (It's too bad that PS/2 ports are not among their selection criteria for motherboards, as they are for keyboards and mice.) A much stronger statement would be to do this with three vendors and say "several vendors", leaving their names to the refs. Jeh ( talk) 21:44, 7 February 2013 (UTC)
Since CN does not mean "I don't think this is true," adding and simultaneously tagging something as CN is not at all disingenuous. Adding new text to WP and adding a "doubtful" tag at the same time would have been disingenuous. But CN and "doubtful" do not mean the same thing.
Regarding the claim itself: I can provide for the "most currently sold keyboards and mice are not PS/2 capable" claim the exact same level of OR that you provided for the "most PCs have PS/2 ports" claim... only mine is from today, not two years ago. If you do the product searches at Newegg you'll find that PS/2-capable (including both PS/2 only and USB+PS/2) keyboards and mice are in the distinct minority. For keyboards, only 177 products out of 810 total are listed as PS/2-capable; for mice, only 27 out of 634.
However, even though that result supports the claim, it's not cite-able, any more than your survey is. A CN tag is therefore still needed. But the claim is now supported at least as well as the "most motherboards" claim, so can I expect that you will not delete it again? If not you'll be quite inconsistent. Jeh ( talk) 08:36, 6 February 2013 (UTC)
As I have explained, my own protocols do allow for adding such material with a CN tag. My OR can establish believability, plausibility, likelihood, etc. But not verifiability. Jeh ( talk) 20:31, 7 February 2013 (UTC)
IMHO this wire color table should be removed completely. There are no standards or conventions for these things in the kinds of places where cheap commodity consumer goods (like computer keyboards) are made. This is just confusing to people who come here and need that kind of information most. The very presence of multiple combinations should be a clue that this isn't really any kind of reliable information. At best, it is a collection of random anecdotes. If people want to know which color is which signal, they should be instructed to verify the pin assignments on the connector. That is the ONLY place that is guaranteed to be correct. Even the silk screen nomenclature on the PC board internal to the keyboard has been known to be incorrect. Rcrowley7 ( talk) 20:07, 21 September 2010 (UTC)
Both use 5V DC, how can there be different voltage through an adapter? Zac67 ( talk) 19:35, 26 May 2011 (UTC)
While hot-plugging is not supported and the system may not detect the new (or even old) device, it can usually be accommodated by pressing the reset button, causing the motherboard to POST and pick up the device on hard-reboot. Synetech ( talk) 19:03, 20 June 2011 (UTC)
I’ve noticed that newer motherboards tend to have a single combined (half-green, half-purple) PS/2 port instead of separate ones. I’ve read conflicting information on what exactly they are for. Some people say that they make you choose either a PS/2 keyboard or a PS/2 mouse and have to use a USB one of the other, while (more) people say that you can use a PS/2 splitter (like the kind that laptop users sometimes use) to plug both devices into the dual-port. Motherboard manuals seem to vague or even lacking in their discussion of the combo-port.
It would be good if someone with a definitive answer could add it to the article. Synetech ( talk) 19:03, 20 June 2011 (UTC)
There's note, that windows input driver v.8 no longer supports PS/2, but this topic Input and HID - Architecture and Driver Support shows the opposite. — Preceding unsigned comment added by Bigbes ( talk • contribs) 10:56, 31 December 2011 (UTC)
I seem to remember that the legacy I/O devices take up valuable IRQs. A floppy, a COM port, a Keyboard socket and a mouse socket will take one interrupt each. Several devices can be attached to one USB bus and only take up one interrupt, although they may not perform as fast eg when using a keyboard for gaming. — Preceding unsigned comment added by 92.26.151.41 ( talk) 23:23, 22 January 2012 (UTC)
I have a Deltaco external hard disk case, and its DC connector is just similar to PS/2, I tested it and a mouse connector fits perfectly. This article has nothing to say about power cable usage. 85.217.42.90 ( talk) 17:09, 8 September 2013 (UTC)
Anent the above, this article is not so much about the physical connector (which, as the IP above pointed out, is used for other things, even in this exact configuration, the standard 6-pin type). It is about the signals and protocols and pinout that appear on the connector in this particular usage. Note that the articles on Serial port and RS-232 are not called "Serial connector" or "RS-232 connector".
Accordingly, I think this article would be better named "PS/2 port". I so propose. Please discuss. Jeh ( talk) 17:44, 8 September 2013 (UTC)
I call one of these things a “PS/2 port”, and so am in favor of such a change. TOOGAM ( talk) 17:56, 16 October 2013 (UTC)
The Mini-DIN connector is the physical connector. A PS/2 connector is simply a Mini-DIN connector using specific signals and protocols. So I think the terms PS/2 connector and PS/2 port are just synonyms that mean the same thing, as are Serial connector and Serial port. – Wbm1058 ( talk) 14:13, 15 September 2014 (UTC)
The article notes that a number of peripherals were shipped with a chipset smart enough to detect whether it was plugged into a ps/2 port or a usb port and could auto-switch between the two, and that such devices generally had usb connectors on them, plus a passive usb to ps/2 adaptor. Is the reverse ever true? Are there devices that have an auto-detecting chipset and a ps/2 plug on them and a passive connector with a ps/2 socket and a usb plug? And are these passive connectors, either usb-plug-becomes-ps/2 plug or ps/2-plug-becomes-usb-plug (if those exist) interchangeable, or is there more than one possible pinout? -- Akb4 ( talk) 04:35, 5 December 2013 (UTC)
I read this as hearsay all the time over the internet and I am perplexed because it simply can't be a hard rule. The USB keyboard I use myself, Microsoft Sidewinder X4, manages to get around this mythical limit somehow, and it isn't simply due to their special keyboard software because it retains its ability to recognize like 15 keys at once in Linux as well.
Furthermore the "source" used to back this statement up is a link to another wiki. 174.45.212.205 ( talk) 01:36, 1 February 2014 (UTC)
In the "port availability" section:
> PS/2 mouse and keyboard connectors have also been used in non-IBM PC-compatible computer systems,
This reads as (non-IBM) (PC-compatible computer systems), when in fact it is trying to say (non-(IBM PC)-compatible) (computer systems).
96.50.85.160 ( talk) 20:18, 8 April 2014 (UTC)
Hello fellow Wikipedians,
I have just modified one external link on PS/2 port. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:
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In the Communication Protocol section, it says "To send a byte of data back to the keyboard, the computer pulls Clock low, waits briefly, then toggles it with a clock signal generated by the computer, while outputting a frame of bits on the Data line, one bit per Clock pulse, (...). The computer releases the Clock line when it is done.".
Does this imply that the host generates the clock while in host-to-device transmission?
Other sources [1][2][3][4] say that the device is always responsible for generating the clock cycle. When the host wants to transmit, it first pulls the CLOCK low to inhibit the transmission from the device, then it pulls DATA low, releases CLOCK and waits for the device to start generating the clock pulse.
[1] https://www.avrfreaks.net/sites/default/files/PS2%20Keyboard.pdf
[2] http://www.networktechinc.com/ps2-prots.html
[3] http://www.mcamafia.de/pdf/ibm_hitrc07.pdf
[4] https://web.archive.org/web/20180830070412/http://retired.beyondlogic.org/keyboard/keybrd.htm
Obs.: References [3] and [4] are included as references for this article.
I don't know if it is the case, but maybe the host is responsible for generating the clock on an older PS/2 protocol that I am not aware of? If not then the text should be corrected. — Preceding unsigned comment added by 2A00:1398:4:3601:D37B:883D:9C3E:8857 ( talk) 21:38, 28 December 2020 (UTC)
whereas the other three sources all agree that on host-to-device transmission, data is clocked in on rising edges instead. Digital Brains ( talk) 11:31, 17 January 2021 (UTC)This bit will be read into the keyboard on the next falling edge, after which you can place the next bit of data.
When I came across this article I was surprised by the statement that motherboards still commonly include a PS2 port. I checked and as of 2022 this is correct, however as this is date relevant and the ports will most likely disappear or become less common at some point in the future then the statement will then no longer be true. Therefore I have added a date when this is known to be true. This should be updated in the future if the interface continues to be fitted to motherboards. Lkingscott ( talk) 07:32, 29 September 2022 (UTC)
This article is rated C-class on Wikipedia's
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Yes, it really is true -- at least on some older motherboards, unplugging a PS/2 device while powered will occasionally at least semi-permanently break the motherboard, such as blowing a special fuse. - 69.87.204.161 01:03, 19 March 2007 (UTC)
I corrected some spelling errors. jpoke89 ( talk) 11:49, 22 November 2007 (UTC)
Care should be taken to avoid connecting a keyboard to a mouse port or vice versa.[citation needed]
That's BS. Electrically they're the same. They signal the same. On all modern motherboards both ports even go to the same chip. The data format is different, but you won't harm or break anything by plugging the wrong thing into the wrong port. —Preceding unsigned comment added by 72.29.167.236 ( talk) 19:22, 20 September 2008 (UTC)
Interestingly the 1st reference on this subject appears to be a comment, rather than a reference... PrimalBlueWolf ( talk) 10:59, 25 March 2020 (UTC)
What was the connector used in the original IBM PC? Family Guy Guy ( talk) 04:34, 19 November 2008 (UTC)
The article should contain a section in which the compatibility of PS/2-to-USB and vice versa is discuessed. Simple adapters exist both for plugging PS/2-hardware into USB sockets, as well as for plugging USB-hardware into PS/2 sockets. -- Alexey Topol ( talk) 16:31, 27 March 2010 (UTC)
Really? I've not bought a retail PC for years but almost no mobo's for self build had PS/2 ports when I was self building in '08. Anyone else think this is a bit out dated and that now almost all KB and mouse are usb as well as PS/2 being largely dropped from new pc's? —Preceding unsigned comment added by 77.197.60.204 ( talk) 12:38, 25 August 2010 (UTC)
T O T A L |
PS/2 | |||
---|---|---|---|---|
# W I T H O U T |
% W I T H | |||
AMD | 148 | 3 | 98 | 95 |
Intel | 317 | 23 | 93 |
I went through every AMD and Intel mobo listing at newegg.com the other day before I removed the (unreferenced) blurb about PS/2 ports "frequently" not being included (results at left).
I didn't bother with the "Motherboard / CPU / VGA Combo" and "Server Motherboards" categories, but 100% of the "Top Sellers" in them have PS/2 ports.
As for retail PCs, I bought a compact tower
Acer from BestBuy last year that has seven USB ports and individual PS/2 ports for keyboard and mouse (as well as many other ports). ¦
Reisio (
talk) 23:29, 7 January 2011 (UTC)
Consensus is determined by the quality of the arguments given on the various sides of an issue, as viewed through the lens of Wikipedia policy.
Wikipedia is not an experiment in democracy or any other political system. Its primary (though not exclusive) means of decision making and conflict resolution is editing and discussion leading to consensus—not voting.
Consensus among a limited group of editors, at one place and time, cannot override community consensus on a wider scale. For instance, unless they can convince the broader community that such action is right, participants in a WikiProject cannot decide that some generally accepted policy or guideline does not apply to articles within its scope.
Would you accept a wording change to something like "PS/2 connectors are still present on some current PCs and component motherboards"? I believe that that claim is sufficiently noncontroversial that a citation is not needed. I would also ask that you not delete my add regarding availability of new PS/2 compatible mice and keyboards. No, it is not proven, but that is what a CN tag is for. Jeh ( talk) 02:21, 6 February 2013 (UTC)
But there is a citable source for "some", whereas there is none for "most". Jeh ( talk) 21:54, 7 February 2013 (UTC)
CN means "it may be that this claim is true, but no reliable, published sources were given to verify it and the information is not considered common knowledge". That is a direct quote from the template description. It goes on to say that the template should be used "when there is a general question of the verifiability of a statement, or when an editor believes that a reference verifying the statement should be provided."
This is why I insist on a CN tag for your "most." You see, the CN tag does not mean "I claim it's not true." It does not even mean "I'm doubtful about this." (There is a "doubtful" tag for that.) I'm saying it's not self-evident the way "the sky is blue" is, nor common knowledge like "the moon orbits the Earth" is, so by WP:V it needs to be cited. And the survey you did two years ago, while providing sufficient motivation for the inclusion of the claim, is not something that we can use as a citation nor sufficient to remove the CN tag.
If I thought the "most motherboards" claim wasn't true I'd have used a "doubtful" tag instead. That validity of the claim is not what this dispute is about. The fact that it lacks a citation is. Jeh ( talk) 08:36, 6 February 2013 (UTC)
No, I'm not ignoring you. I'm trying to get you to see that you can't simply ignore WP policy. The "self-evidentiary" nature of your claim is not what is under discussion. What is relevant to inclusion on Wikipedia is whether it is verifiable.
I'm afraid that words like "reliable source", "published", and "verifiable" do indeed have specific meanings in the context of WP policy. And regardless of how they are used elsewhere, when writing for WP and defending your work here, you must use WP's meanings. Otherwise your position here may be indefensible.
In particular, you write "The validity is the only thing that matters." I tell you three times: WP policy disagrees with you. WP:V states that all material added to WP must be verifiable, according to WP's definition of "verifiable", from what WP considers "reliable, published sources." Otherwise it can't be here, no matter how true it is, no matter how true you "know" it is, no matter how satisfied you are from your own research. That's WP:V in a nutshell. And there is no provision I can find that would allow any other policy to override that.
I really think you need to read all of WP:V, and as well, the essay "verifiability, not truth") for some of the rationale behind it.
And then you need not to say "but, I can ignore all that, because I know this claim is true."
Similarly the criteria for "reliable" generally excludes self-published sources (like online catalogs); see WP:RS.
However! I think I found an "out". WP:RS does allow that "Self-published or questionable sources may be used as sources of information about themselves" (emph. added). So a statement along the lines of "At least one PS/2 port can be found on most of the component motherboards offered by one on-line vendor", with a link to Newegg's "motherboards" listings, seems to me to be acceptable. (It's too bad that PS/2 ports are not among their selection criteria for motherboards, as they are for keyboards and mice.) A much stronger statement would be to do this with three vendors and say "several vendors", leaving their names to the refs. Jeh ( talk) 21:44, 7 February 2013 (UTC)
Since CN does not mean "I don't think this is true," adding and simultaneously tagging something as CN is not at all disingenuous. Adding new text to WP and adding a "doubtful" tag at the same time would have been disingenuous. But CN and "doubtful" do not mean the same thing.
Regarding the claim itself: I can provide for the "most currently sold keyboards and mice are not PS/2 capable" claim the exact same level of OR that you provided for the "most PCs have PS/2 ports" claim... only mine is from today, not two years ago. If you do the product searches at Newegg you'll find that PS/2-capable (including both PS/2 only and USB+PS/2) keyboards and mice are in the distinct minority. For keyboards, only 177 products out of 810 total are listed as PS/2-capable; for mice, only 27 out of 634.
However, even though that result supports the claim, it's not cite-able, any more than your survey is. A CN tag is therefore still needed. But the claim is now supported at least as well as the "most motherboards" claim, so can I expect that you will not delete it again? If not you'll be quite inconsistent. Jeh ( talk) 08:36, 6 February 2013 (UTC)
As I have explained, my own protocols do allow for adding such material with a CN tag. My OR can establish believability, plausibility, likelihood, etc. But not verifiability. Jeh ( talk) 20:31, 7 February 2013 (UTC)
IMHO this wire color table should be removed completely. There are no standards or conventions for these things in the kinds of places where cheap commodity consumer goods (like computer keyboards) are made. This is just confusing to people who come here and need that kind of information most. The very presence of multiple combinations should be a clue that this isn't really any kind of reliable information. At best, it is a collection of random anecdotes. If people want to know which color is which signal, they should be instructed to verify the pin assignments on the connector. That is the ONLY place that is guaranteed to be correct. Even the silk screen nomenclature on the PC board internal to the keyboard has been known to be incorrect. Rcrowley7 ( talk) 20:07, 21 September 2010 (UTC)
Both use 5V DC, how can there be different voltage through an adapter? Zac67 ( talk) 19:35, 26 May 2011 (UTC)
While hot-plugging is not supported and the system may not detect the new (or even old) device, it can usually be accommodated by pressing the reset button, causing the motherboard to POST and pick up the device on hard-reboot. Synetech ( talk) 19:03, 20 June 2011 (UTC)
I’ve noticed that newer motherboards tend to have a single combined (half-green, half-purple) PS/2 port instead of separate ones. I’ve read conflicting information on what exactly they are for. Some people say that they make you choose either a PS/2 keyboard or a PS/2 mouse and have to use a USB one of the other, while (more) people say that you can use a PS/2 splitter (like the kind that laptop users sometimes use) to plug both devices into the dual-port. Motherboard manuals seem to vague or even lacking in their discussion of the combo-port.
It would be good if someone with a definitive answer could add it to the article. Synetech ( talk) 19:03, 20 June 2011 (UTC)
There's note, that windows input driver v.8 no longer supports PS/2, but this topic Input and HID - Architecture and Driver Support shows the opposite. — Preceding unsigned comment added by Bigbes ( talk • contribs) 10:56, 31 December 2011 (UTC)
I seem to remember that the legacy I/O devices take up valuable IRQs. A floppy, a COM port, a Keyboard socket and a mouse socket will take one interrupt each. Several devices can be attached to one USB bus and only take up one interrupt, although they may not perform as fast eg when using a keyboard for gaming. — Preceding unsigned comment added by 92.26.151.41 ( talk) 23:23, 22 January 2012 (UTC)
I have a Deltaco external hard disk case, and its DC connector is just similar to PS/2, I tested it and a mouse connector fits perfectly. This article has nothing to say about power cable usage. 85.217.42.90 ( talk) 17:09, 8 September 2013 (UTC)
Anent the above, this article is not so much about the physical connector (which, as the IP above pointed out, is used for other things, even in this exact configuration, the standard 6-pin type). It is about the signals and protocols and pinout that appear on the connector in this particular usage. Note that the articles on Serial port and RS-232 are not called "Serial connector" or "RS-232 connector".
Accordingly, I think this article would be better named "PS/2 port". I so propose. Please discuss. Jeh ( talk) 17:44, 8 September 2013 (UTC)
I call one of these things a “PS/2 port”, and so am in favor of such a change. TOOGAM ( talk) 17:56, 16 October 2013 (UTC)
The Mini-DIN connector is the physical connector. A PS/2 connector is simply a Mini-DIN connector using specific signals and protocols. So I think the terms PS/2 connector and PS/2 port are just synonyms that mean the same thing, as are Serial connector and Serial port. – Wbm1058 ( talk) 14:13, 15 September 2014 (UTC)
The article notes that a number of peripherals were shipped with a chipset smart enough to detect whether it was plugged into a ps/2 port or a usb port and could auto-switch between the two, and that such devices generally had usb connectors on them, plus a passive usb to ps/2 adaptor. Is the reverse ever true? Are there devices that have an auto-detecting chipset and a ps/2 plug on them and a passive connector with a ps/2 socket and a usb plug? And are these passive connectors, either usb-plug-becomes-ps/2 plug or ps/2-plug-becomes-usb-plug (if those exist) interchangeable, or is there more than one possible pinout? -- Akb4 ( talk) 04:35, 5 December 2013 (UTC)
I read this as hearsay all the time over the internet and I am perplexed because it simply can't be a hard rule. The USB keyboard I use myself, Microsoft Sidewinder X4, manages to get around this mythical limit somehow, and it isn't simply due to their special keyboard software because it retains its ability to recognize like 15 keys at once in Linux as well.
Furthermore the "source" used to back this statement up is a link to another wiki. 174.45.212.205 ( talk) 01:36, 1 February 2014 (UTC)
In the "port availability" section:
> PS/2 mouse and keyboard connectors have also been used in non-IBM PC-compatible computer systems,
This reads as (non-IBM) (PC-compatible computer systems), when in fact it is trying to say (non-(IBM PC)-compatible) (computer systems).
96.50.85.160 ( talk) 20:18, 8 April 2014 (UTC)
Hello fellow Wikipedians,
I have just modified one external link on PS/2 port. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:
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Cheers.— InternetArchiveBot ( Report bug) 11:32, 5 December 2017 (UTC)
In the Communication Protocol section, it says "To send a byte of data back to the keyboard, the computer pulls Clock low, waits briefly, then toggles it with a clock signal generated by the computer, while outputting a frame of bits on the Data line, one bit per Clock pulse, (...). The computer releases the Clock line when it is done.".
Does this imply that the host generates the clock while in host-to-device transmission?
Other sources [1][2][3][4] say that the device is always responsible for generating the clock cycle. When the host wants to transmit, it first pulls the CLOCK low to inhibit the transmission from the device, then it pulls DATA low, releases CLOCK and waits for the device to start generating the clock pulse.
[1] https://www.avrfreaks.net/sites/default/files/PS2%20Keyboard.pdf
[2] http://www.networktechinc.com/ps2-prots.html
[3] http://www.mcamafia.de/pdf/ibm_hitrc07.pdf
[4] https://web.archive.org/web/20180830070412/http://retired.beyondlogic.org/keyboard/keybrd.htm
Obs.: References [3] and [4] are included as references for this article.
I don't know if it is the case, but maybe the host is responsible for generating the clock on an older PS/2 protocol that I am not aware of? If not then the text should be corrected. — Preceding unsigned comment added by 2A00:1398:4:3601:D37B:883D:9C3E:8857 ( talk) 21:38, 28 December 2020 (UTC)
whereas the other three sources all agree that on host-to-device transmission, data is clocked in on rising edges instead. Digital Brains ( talk) 11:31, 17 January 2021 (UTC)This bit will be read into the keyboard on the next falling edge, after which you can place the next bit of data.
When I came across this article I was surprised by the statement that motherboards still commonly include a PS2 port. I checked and as of 2022 this is correct, however as this is date relevant and the ports will most likely disappear or become less common at some point in the future then the statement will then no longer be true. Therefore I have added a date when this is known to be true. This should be updated in the future if the interface continues to be fitted to motherboards. Lkingscott ( talk) 07:32, 29 September 2022 (UTC)