No PS2 port for keyboard; any adapters allowing for hardware interupt?

[Typhoon859]

The main goal here is to achieve as little latency as possible, which to my knowledge is (up to) 5ms. From all I've read, it seems to me that for consistency, it's only possible with a PS/2 connection to the motherboard. There are of course some other benefits to that as well. Are there any options I would have for getting this, whether it's some sort of a work around for actual PS/2 input or a completely alternate solution?.. Thanks guys.

I've searched for everything I could find - everywhere, for any idea/solution that may work. USB converters would obviously defeat the purpose here since I want to achieve at least that 5ms standard, DB9 adapters I've actually found I doubt would even work, and PCI cards that I've found simply utilize the USB protocol as well, just adapted through PCI..


PS- As to why I need such low latency (and it's not for gaming), my reply would only bear more questions, so if my word could just be taken for why there's the need, that would greatly be appreciated.

 

[ssddx]

the biggest reason why ps/2 is considered superior is because it force-interrupts on key press so that the input gets processed immediately while usb gets put into the usb stack. this is why usb keyboards list polling rates which send a signal no matter if there is input signal or not. while this works if you are heavily utilizing the usb bus there could be some delay.

using a usb keyboard with a usb to ps/2 adapter should work fine provided the keyboard works with ps/2. some keyboards (such as the razer mechanical keyboards) do not work with usb-ps/2 adapters.

at 1000hz polling there is a signal being sent every .001s which is far below your requirements. now realize there could be some delay because of processing of this signal due to the usb bus being bogged down or from slow hardware but in general you should have a response time which is imperceptible to you.

an average time to blink is around 400ms and the average reaction time is 215ms. current ps/2 and usb keyboard reaction times are more than sufficient for ANY type of work being done.

a description of why you need such low latency would definitely be helpful.

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things which affect latency:

-your reaction time
-time for you to depress the key
-time for the signal to be sent
-time for the signal to be processed
-time for the program to process the signal
-time for the program to generate video feed (if applicable)
-time for the video feed to be transmitted to the monitor (if applicable)
-time for the video feed to be displayed by the monitor (if applicable)

the actual speed of the ps/2 port is just one (small) part of the equation.

so again, if you would enlighten us to why you are so concerned we may be able to give you a better answer (or at least an answer tailored to your situation).

 

[Typhoon859]

the biggest reason why ps/2 is considered superior is because it force-interrupts on key press so that the input gets processed immediately while usb gets put into the usb stack. this is why usb keyboards list polling rates which send a signal no matter if there is input signal or not. while this works if you are heavily utilizing the usb bus there could be some delay.

using a usb keyboard with a usb to ps/2 adapter should work fine provided the keyboard works with ps/2. some keyboards (such as the razer mechanical keyboards) do not work with usb-ps/2 adapters.

at 1000hz polling there is a signal being sent every .001s which is far below your requirements. now realize there could be some delay because of processing of this signal due to the usb bus being bogged down or from slow hardware but in general you should have a response time which is imperceptible to you.

an average time to blink is around 400ms and the average reaction time is 215ms. current ps/2 and usb keyboard reaction times are more than sufficient for ANY type of work being done.

a description of why you need such low latency would definitely be helpful.

---

things which affect latency:

-your reaction time
-time for you to depress the key
-time for the signal to be sent
-time for the signal to be processed
-time for the program to process the signal
-time for the program to generate video feed (if applicable)
-time for the video feed to be transmitted to the monitor (if applicable)
-time for the video feed to be displayed by the monitor (if applicable)

the actual speed of the ps/2 port is just one (small) part of the equation.

so again, if you would enlighten us to why you are so concerned we may be able to give you a better answer (or at least an answer tailored to your situation).

I've read that with keyboards, a polling rate past 200 Hz doesn't make a difference for some reason. I can't quite recall but I think it had something to do with the fact that it also buffers some amount of keys you press per certain amount of allotted time. With a PS/2 connection, I don't think it gets faster but it processes it directly, one key at a time, and there's no chance of the problems that there could be with USB. This is the kind of advantage I need.

In terms of why I need this, if you really have to know, it's not to do with visual reaction time, but with sound reaction time. To that, although unknown to our outward perception, it's much more accurate than anything else. I would be using the keyboard to trigger events, cuts, pauses, and/or stops, all of which will be recorded, and even the slightest difference is large enough for digital solution to not be so reliable. At the very least, I'd have the comfort of knowing that it completely boils down to just me, and not any kind of hardware delays. Thank you.

PS- I posted this in multiple locations; I'm not sure why I didn't get back to you with a response. Perhaps I didn't get an e-mail notification. Sorry that it took so long; I actually haven't found a solution still and I'm back to trying to figure this out. In any case, in the future, pretty much no motherboards will have PS/2 ports built in anyway.

 

[ssddx]

the reason why ps2 is considered superior is because it is force interrupt based which means it does not go into the usb stack to be processed "whenever" it gets to it in the stack. granted this delay (if any) if often minimal but given the option i would go with ps2 as well.

if your keyboard is usb and is lacking a ps2 connection but your motherboard supports ps2 then there are adapters out there. personally i just use one that looks like this..

and it has always worked fine for me. keep in mind that not all keyboards are usable in this manner however (razer keyboards dont work for example.)

if your keyboard has ps2 but your motherboard only has usb then perhaps look into a pci card with ps2 ports. i am not sure if they work quite as well as the integrated solution though as i have no experience with them.

if you have a usb keyboard and usb motherboard... well you could do a combination of the above if you want ps2 that badly. the only case where usb would be an inferior solution is when you have the usb bus jammed. eg if you had multiple usb hard drives hooked up and were transferring files but even then it might not be a big deal depending on how the system handles the usb stack.

 

[Typhoon859]

the reason why ps2 is considered superior is because it is force interrupt based which means it does not go into the usb stack to be processed "whenever" it gets to it in the stack. granted this delay (if any) if often minimal but given the option i would go with ps2 as well.

if your keyboard is usb and is lacking a ps2 connection but your motherboard supports ps2 then there are adapters out there. personally i just use one that looks like this..

and it has always worked fine for me. keep in mind that not all keyboards are usable in this manner however (razer keyboards dont work for example.)

if your keyboard has ps2 but your motherboard only has usb then perhaps look into a pci card with ps2 ports. i am not sure if they work quite as well as the integrated solution though as i have no experience with them.

if you have a usb keyboard and usb motherboard... well you could do a combination of the above if you want ps2 that badly. the only case where usb would be an inferior solution is when you have the usb bus jammed. eg if you had multiple usb hard drives hooked up and were transferring files but even then it might not be a big deal depending on how the system handles the usb stack.

Oh, well right, the problem is exactly that my motherboard doesn't have a PS/2 slot. I mean, it says it right there in the title. None of the PCI solutions actually integrate PS/2 into the motherboard. They're all basically USB adapters.

In my case, the USB problem might especially be true considering the insane amount of USB devices I have plugged in/in use. There lies the problem but either way, as you said yourself, I'd prefer a PS/2 connection regardless and this problem is one to think about since as I said, in the future, there won't even be ANY motherboards that have this connection.

 

[ssddx]

even some brand spankin new z87 boards have a single ps2 connection. you may need to buy an upper level or enthusiast product to get it though.

if you are worried about it then you could always get a different motherboard than what you have now as that is the only real solution to have it fully integrated.

personally i wouldnt worry about it UNLESS you have a problem as you very well could experience no issues at all. buying a new motherboard is not exactly a cheap fix and i would suggest waiting to see if you definitely have problems before going out and doing this.

i'm not familiar with exactly how the usb stack works (i get the concept but dont know all the coding and ins and outs of the system) but perhaps a pci card with usb ports would be classified in a different usb stack hence eliminating the variable of multiple drives using usb at once. you may need to ask this in the windows subsection as i cant tell you whether this would work or not.

i highly doubt ps2 will ever truly go away. at least not until there is a solution which works in the same manner. computer enthusiasts (myself included) demand lag free play so my guess would be that top end motherboards marketed towards enthusiasts or gamers will include at least one port. i know for a fact the z87 maximus v extreme has one and it just came out.

 

[Typhoon859]

even some brand spankin new z87 boards have a single ps2 connection. you may need to buy an upper level or enthusiast product to get it though.

if you are worried about it then you could always get a different motherboard than what you have now as that is the only real solution to have it fully integrated.

personally i wouldnt worry about it UNLESS you have a problem as you very well could experience no issues at all. buying a new motherboard is not exactly a cheap fix and i would suggest waiting to see if you definitely have problems before going out and doing this.

i'm not familiar with exactly how the usb stack works (i get the concept but dont know all the coding and ins and outs of the system) but perhaps a pci card with usb ports would be classified in a different usb stack hence eliminating the variable of multiple drives using usb at once. you may need to ask this in the windows subsection as i cant tell you whether this would work or not.

i highly doubt ps2 will ever truly go away. at least not until there is a solution which works in the same manner. computer enthusiasts (myself included) demand lag free play so my guess would be that top end motherboards marketed towards enthusiasts or gamers will include at least one port. i know for a fact the z87 maximus v extreme has one and it just came out.

Actually, that's not exactly the case. Buying a new motherboard would be a solution as you say except for that it wouldn't. Out of all the motherboards, I have the only one which fits the criteria I need, PS/2 not included. I thought I'd be able to find a workaround as it didn't seem like something that could be a problem. I needed a motherboard that has two ethernet ports and 10+ SATA connections. The space I have/use is crucial to me and all my HDD's and other SATA connections needed to fit in one case. This is a high-end motherboard and it was brought to my attention that the opposite was true in terms of motherboards being equipped with PS/2. The more a motherboard had bundled with it, the less likely it was to come equipped with a PS/2 port. I know they still exist but they don't mass produce a product for only a fraction of a percent who care about such an out-of-date connection. They do it now simply because they still can. In my case, the tradeoffs for another motherboard wouldn't be worth it. The point furthermore wouldn't be to argue that, "well, that's that then." The point was and still is about actually finding a way to get the functional benefits of the PS/2 serial connection.

Thank you for your contribution to the conversation, but if you don't know, it's not otherwise for you to decide how this should then be handled. I would appreciate some respect for my understanding of what's best for me, whether it be how to built my system or where to post my inquiries. I understand your intention wasn't to suggest this but that is all one can get out of your provided statements. Thanks again for your time though.

 

[ssddx]

I would appreciate some respect for my understanding of what's best for me, whether it be how to built my system or where to post my inquiries.

the reason i suggested waiting until you actually had a problem is to save you expense and grief. unless of course that you already do know you have a problem from testing but did not list that. from your post it sounds as if you are worried about a problem that could happen not one that exists currently. please specify.

i was giving you options to pursue and research not telling you what to do. perhaps you would have preferred zero responses and zero options? while perhaps not all suggestions turn into answers it at least narrows down what will not work.

i told you to ask the question on usb stacks in the windows forum quite simply because you may get an answer in 1-2 days while in this subsection it may take 6 months or never. excuse me for trying to save you time and grief but i've seen it before.

please dont insult the help. we do this because we like to not because we are paid. just as you say you want respect do realize that so do we.

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you never did state what hardware you were running which should have been in your very first post. i can only guess as to what your processor and system specs are.....

http://www.newegg.com/Product/Product.aspx?Item=N82E16813157371&nm_mc=AFC-C8Junction&cm_mmc=AFC-C8Junction-_-na-_-na-_-na&cm_sp=&AID=10446076&PID=3938566&SID=
ps2 port
2 lan ports
10 sata ports

looks to have everything you listed. all i'm saying is that there are likely options out there if you wanted to upgrade the mobo. its also quite a bit easier to add other drives by adding a pci sata card than to try and add ps2 via pci as it doesnt quite work out that way.

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http://www.computercablestore.com/PC_Insert_PS2_Port_2x4_pi_PID1018.aspx

i've heard that some motherboards without a ps2 port may still have a 2x4 (8pin) port on the motherboard for connecting a ps2 port. i dont know about your model since you never listed it.

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you may want to check on the usb stack situation with adding a pci usb card. perhaps it may work perhaps not.

 

[Typhoon859]

I would appreciate some respect for my understanding of what's best for me, whether it be how to built my system or where to post my inquiries.

the reason i suggested waiting until you actually had a problem is to save you expense and grief. unless of course that you already do know you have a problem from testing but did not list that. from your post it sounds as if you are worried about a problem that could happen not one that exists currently. please specify.

i was giving you options to pursue and research not telling you what to do. perhaps you would have preferred zero responses and zero options? while perhaps not all suggestions turn into answers it at least narrows down what will not work.

i told you to ask the question on usb stacks in the windows forum quite simply because you may get an answer in 1-2 days while in this subsection it may take 6 months or never. excuse me for trying to save you time and grief but i've seen it before.

please dont insult the help. we do this because we like to not because we are paid. just as you say you want respect do realize that so do we.

--------------------------------------------------------

you never did state what hardware you were running which should have been in your very first post. i can only guess as to what your processor and system specs are.....

http://www.newegg.com/Product/Product.aspx?Item=N82E16813157371&nm_mc=AFC-C8Junction&cm_mmc=AFC-C8Junction-_-na-_-na-_-na&cm_sp=&AID=10446076&PID=3938566&SID=
ps2 port
2 lan ports
10 sata ports

looks to have everything you listed. all i'm saying is that there are likely options out there if you wanted to upgrade the mobo. its also quite a bit easier to add other drives by adding a pci sata card than to try and add ps2 via pci as it doesnt quite work out that way.

--------------------------------------------------------

http://www.computercablestore.com/PC_Insert_PS2_Port_2x4_pi_PID1018.aspx

i've heard that some motherboards without a ps2 port may still have a 2x4 (8pin) port on the motherboard for connecting a ps2 port. i dont know about your model since you never listed it.

--------------------------------------------------------

you may want to check on the usb stack situation with adding a pci usb card. perhaps it may work perhaps not.

I'd be interested to know how I've insulted you in particular, but ok. I thanked you for the help, and obviously I know it's not for pay. You seemed to be ignoring any input or information I was giving and simply stating all the logic I went through before I made my post, that which I've implied I did before. Sorry for being blunt, but you didn't leave me much of a choice.

I mentioned what was needed and I was asking for a solution to that, not alternate scenarios where that wouldn't be an issue. That's why in no way did I see how my hardware was relevant, and plus, up to that point, I stated everything you asked for anyway. I appreciate your time, as was stated sincerely either way, but apparently it took getting you a bit stirred for whatever reason for you to actually respond to the direct comments made.

In any case, I in particular decided to go with the GIGABYTE GA-Z77X-UD5H motherboard because of its PCI configuration and because I simply like the manufacturer better and the drivers/software they make with it. I figured that to trade off a PCI-e slot for a PS/2 port wouldn't be worth it. This situation I think was the same with the previous generation. I once again appreciate your time in finding this solution which meets my previously stated criteria, but I've been trying to get across that there should be the assumption made that I am at the point at which I am for a reason, and that the issue at hand should be taken as a legitimate problem to solve and not something which can/could've been otherwise avoided. I hope there's no reason for me to have to state any further my reasons for one thing or another as it would be and has previously taken the conversation backwards. It's like if someone's looking for an amplifier that could drive 600 ohm headphones and me telling them they should just get headphones with a smaller impedance. If the OP stated that he/she has his/her reasons for getting those headphones, I wouldn't go make a post making a statement against that; it's not for me to assume they don't know any better at that point. You may have not been cognitive of this fact or not have done it on purpose, but that's what it was in the end.

As for there being a pin header connection for a PS/2 port, I never even realized! Thank you. That's something entirely new that I haven't run into in all my searching, surprisingly - maybe because it's not common for motherboards to have that. Unfortunately, it looks like my motherboard is one of those many.

Finally, in terms of the whole USB stack thing being a problem or not, I wouldn't be able to tell. Unless there is a way to test the lag between when I press a key on the keyboard and when it registers, it'd likely be below the point at which I can reliably say whether there's lag or not, especially at the point of 5ms+/-, obviously. All I have to go by is the technical information available, which, once again, seems to suggest that with USB, it's 5ms- or more, unreliably, and with PS/2, it's 5ms-, reliably.

Because the following kind of adapters don't exist, I'm guessing it's impossible to adapt the protocol through a PCI slot, though I don't understand why. If it's a parallel connection, a serial connection should definitely be adaptable. I'd understand the problem the other way around, but perhaps the hardware interrupt is the problem and maybe through PCI, without proper available configurations in the BIOS, this might cause potential crashes.

Sorry if I offended you, but I think you could see how some of the input may not have been too sympathetic to my cause as it was stated. In the future, so people don't seem so ungrateful for your input, if there's really something you want to know if the OP is aware of, just ask first and save yourself the trouble. One doesn't have to be entirely grateful for every bit of the input to be appreciative of all the time, if you doubted my sincerity.

 

[ssddx]

the only reason i took offense is because you accused me of trying to tell you what to do, how to do it and where to do it at.

all i list are possible suggestions. honestly its completely up to you if you want to pursue them or not

i do realize that you are gratefull for the information. i just dont like being accused of something i didnt do and i may have overreacted about it but its one of those things i am bothered by. again, perhaps insulted is too harsh a word but i suppose you can see now why i may have thought so.

yes i listed some of what you have already looked into however not knowing the specifics of your hardware or what you are trying to do i must list them in case you just overlooked them as a possible solution. there are specific reasons why i have listed solutions you have already tried and thrown out so please do bear with me.

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seeing as how you want to be blunt...

i realize that you want a perfect solution to your problem but....no, i've never seen or heard of any product which can perfectly replicate the effects of ps/2 on a system without ps/2 capability and i've been actively into computers and technology for quite a long time. i believe the reason for this is due to how ps/2 works which i will list in this post.

i know you do not want to see alternate scenarios but do realize that if your perfect solution doesnt exist and you still want a solution that you may end up needing those alternate scenarios.

i do believe that ps/2 is becoming an issue only quite recently which is why many of us may not know of a good workaround. the other reason is that in most cases there is not a problem with usb. of course there will always be those who do and unfortunately its often up to them to figure out what to do about it which is what you are doing right now.

i'll try my best to come up with a perfect solution but you must realize that there may not be one. at least not one which works in the exact same way as ps/2 functionality did on pc's past. you may very well have to settle for a solution which is not ideal.

i'm not trying to burst your bubble or discourage you. i am simply stating that your solution may not exist and that you should at least think about what some possible alternatives are if we discover that this is the case.

i will try and be a bit more in depth with a few of my recommendations so that you can figure out why i recommended them even though you mentioned them as solutions you already looked up but dismissed as non-solutions.

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how a ps2 port works is by creating a direct i/o line from the device microcontroller to the microcontroller on the motherboard. it also has to do with IRQ (interrupt requests). on a motherboard with a standard ps/2 port and ps/2 mouse or keyboard connected the device generates its own interrupt request. since there are so many different connected devices it is not possible for all of them to have individual interrupt requests without bogging down the whole system so instead they are split into sections and each one forms a stack to be processed. in a motherboard with a usb keyboard connected the keyboard commands get sent to this usb stack. i believe the usb controller has its own irq.

which leads me to why i suggested a pci usb card. doing this may generate its own IRQ which would act in a similar manner to a ps/2 keyboard having its own IRQ. this option would still need to pass through a usb bus however if i am right then perhaps at least it wouldnt have to deal with an overloaded usb bus and work at the minimum response times that usb is capable of.

diagram of ps/2 vs usb keyboard

what i am not sure about is if adding a pci usb card with its own dedicated controller would add a new IRQ or if it would combine both controllers into one IRQ. this is what i wanted you to ask over in the windows subsection as perhaps someone more literate than I with low-level system operation can come up with an answer to make this a possibility or not.

i've also read about PCI port IRQ sharing. that might add yet another wrench into the equation. yet another question for the others.

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you mentioned a 5ms response time for usb and how this may be an issue.

i'm not sure if you are aware of this or not but in a situation such as waiting for an audio key and pressing a button to generate a stop is comparable to a reaction time test. most users score between 120-350ms for something as simple as clicking a single button in response to a stimulus. this time includes any usb delay, keyboard delay, your own reaction time and the time it takes for your system to process the information.

this is the reason why i asked you to do a test to verify that you did in fact have an issue. on a free and clear system be it ps2 or usb the limiting factor is going to be human response time. this is why i'm thinking that the whole ps/2 vs usb issue isnt really concerning the actual numbers (as they are quite close) but more of the IRQ and stack issue as i stated before.

of course on a crowded usb bus the extra latency might be of more consequence. what exactly do you plan on having hooked up via usb?

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i understand that this generates an alternative scenario where ps/2 isnt an issue but purchasing a motherboard which does have ps/2 function built in while still retaining all of the other features you want from another brand is the only surefire way to get perfect ps/2 performance that i know of.

i also understand that you made your hardware choices for a certain reason and that this may not be an option. unfortunately the ps/2 issue doesnt seem important enough for motherboard manufacturers to retain the ps/2 port or ps/2 port pins on the motherboard to allow for a simple cable and back panel adapter.

personally i think this solution is best saved as a worst case scenario if nothing else works how you want it to.

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i have attempted to research if a single usb port can be given its own IRQ and it looks like it is possible to replicate the ps/2 effect via usb however it appears that there can be extreme lag when doing this in some cases which makes it a non-solution.

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i have found a source which claims that using a keyboard on a ps/2 port has a theoretical maximum of 1500/sec. of course this does not mean that the keyboard is capable of this kind of input. there are however usb keyboards which can reach 1000 polls/sec.

generally since human response time is such a big factor having a keyboard poll this many times is considered useless and it just floods the usb bus.

this is another reason why usb is often not seen as a problem assuming of course that a clogged usb bus isnt an issue.

just for reference 1000/sec is a response every 1ms and 1500/sec is every .6ms. close enough to not even be noticible.

i'm not seeing much of a solution here.

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i even pursued the possible use of your 1394a firewire port for a keyboard however it appears that there are no working adapters and that driver support would be a large issue which makes this a no go.

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it appears that you are correct in that a ps/2 pci card is essentially just a card with a controller which converts the signal to usb.

what i wonder about though is if it uses its own IRQ, a shared pci IRQ or the usb bus IRQ.

perhaps another question for people familiar with IRQ over in the windows section.

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anyways... hope this clarifies why i listed some of the things i did and why it seems i was being counter productive to you.

i'm providing possible fixes because as of this moment i dont have any "perfect solution" answers for you but not for lack of effort.

this post alone took me about an hour to compile with some research on points i was not familiar with. no lack of effort on my part.

 

[Typhoon859]

Wow, well thanks once again for such an in-depth response. As I said, lack of effort is certainly not even a remote accusation I was throwing your way. I understand, nobody likes to be accused of really whatever it may be, especially when trying to help, but that's why I said what I said the way I did initially. I really meant only two things by it. 1), I was trying to suggest more strongly that my reasons for needing a solution like this should be considered final ( and that otherwise, there isn't a real solution then for me). And 2), that you shouldn't trouble yourself further if you didn't know off hand or otherwise knew of what's technically possible. You asked if I would have preferred no answer instead; I wanted to say yes, but at this point, no. Thank you, and you really did make this feel for me like a team effort with someone on my side who has no reason but his own will to help. Sorry if I misinterpreted your intention but if it was your own kind of troubleshooting process, it wasn't clear, so that's why I suggested maybe to ask first in the future rather than to immediately just make the suggestion(s). But anyway, let's forget about that now as this clearly isn't the truth behind the situation and really boils down to having been a misinterpretation. Now I don't accuse you of this, but my perhaps premature frustration came from the fact that there are many times somebody who gives responses, even if in depth, to stroke their own ego, and it usually just ends up derailing the thread for people who would've otherwise seen a very plain situation and would have been able to help. I'm also busy and I always end up having to waste my time just to keep things in perspective on forums because of people who don't take the mental effort to consider all that has been prior said. And btw, that's pretty impressive in an hour; I'm surprised it didn't take longer. Thanks again.

I wish I could tell you more specifically as to how this works, but basically, the problem for me I never thought would've been to have a separate IRQ for the keyboard, because even if that were the case for it and I thought could be accomplished, the issue lies with specifically how the keyboard interfacing is handled within the OS. I read it when looking into the whole polling rates business upon having stumbled upon it's irrelevancy for keyboards. The reason was basically that brief thing that I mentioned about where it basically buffers the input I think and sends out the commands in groups. From having read further, I remember there was no way of changing the buffer size or something because it's somehow fundamental to it's functioning in the first place. Despite the polling rate being 1000, or even 1500 polls/sec, the lowest latency time remains to be with up to 5 ms. That makes it equal to that of a PS/2 connection except for the fact of the potential occasional delay, and considering that it's not perceivable, for the state of mind of knowing that it's consistent, that just wouldn't do for me. At the Windows forum, I guess they could help there to confirm whether the mentioned claim is true or not. This is therefore all carried based on that assumption.

The firewire port I thought would then serve as a perfect alternate solution if I could use it just for the keyboard. As you said however, that's also a non-solution.

I never said I was looking for a "perfect" solution, in the sense of it being a one-to-one replacement for the PS/2 protocol. I was under no illusions and I was and am fully aware of the likeliness of there not being such a fix, any which way, so there isn't really a bubble for you to burst. I'm also not demanding of you a solution that fits my exact criteria; I'm simply saying that you need not concern yourself otherwise or insist on countering what I've dismissed as something that should again be considered/questioned. I see now that's not what you were doing, and I actually appreciate having my ideas challenged, but just not in this kind of forum; pun intended.

I am very aware of the human response time element of which you speak, as I mentioned before, but as I said, it's more to do with my specific application which is to do with audio. You won't find others as crazy as me, but knowing that something is within the realm of possibility for being optimized (especially at no greater cost), the thickheadedness of plowing straight on whilst being aware of this simple fact doesn't sit well with me. It's like watching a 4:3 video stretched to 16:9, or worse, a 16:9 video smushed to 4:3. It drives me crazy seeing somebody watch like that when all it takes is a push of the aspect ratio button usually to fix the problem.

So, it's not like this issue would ruin my creative workflow if I just let it go, considering the small difference there ends up likely being in a practical sense, but I often try to cut something down to as little as 3 ms (it usually seems to be), if possible, so knowing I can accurately do it using only my ears with as minimal a delay as possible takes the worry of my shoulders of having to go and manually fix each cut by at least so and so amount. Also, the difference still amounts to something and as I said, if it can be optimized, why settle for less when you only benefit from it otherwise? In this situation, can't think of a reason.

The closest solution I've found has actually been the USB solution where you can get it to generate its own IRQ. That's probably what I'll end up doing and it doesn't necessarily bog down the system if implemented correctly I think. There are a few options here as I recall, but they were both essentially developed I think for the purposes of N-key rollover; that's how I found out about it and through what I searched. It's not ideal however and it requires a bit of know-how which I don't have. It's not exactly a cheap experiment either, and that's really though what it would be at this point more than anything, an experiment.

Well anyway, you seem to have went through it all. This is pretty much the point that I've gotten to and just, the visual image of somehow connecting a PS/2 port to my system is killing me, lol. It's like... just, plug in! It seems like it should be so simple and I quite honestly didn't expect this. It's pretty much the only thing I think which can't be integrated through PCI and I certainly didn't value the connection more than others which I thought would certainly be harder to adapt through PCI, only to be proven wrong. Its simplicity and the fact that it's so dated is I think what eluded me. So as it turns out, USB was never exactly a real alternate solution for keyboard devices so I'm not sure why it didn't remain to be the accepted norm considering how special it is. I would say things moved towards USB for convenience, but for some time, and still today, pretty much most motherboards still come with a PS/2 connection so that wouldn't exactly be true.

 

[ssddx]

from what i've read adding a seperate IRQ for a usb connected keyboard can be a rather bad thing.

this is why i suggested possibly using a pci usb card which *might* have its own IRQ but i'm not so sure.

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truthfully i dont think it will be much of a hardware problem and is mostly just a psychological "but i know its there and it really bothers me" problem. sort of like having a large hole in the floor under your kitchen cabinets. it doesnt affect anything for the most part but it can still drive you nuts. sometimes we just want it fixed for peace of mind.

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reaction time to audio and visual stimulus is going to be similar. my only point was that its pretty much impossible to get closer to the target mark then your reaction speed and that 5ms isnt really going to matter either way.

yes, i realize its more piece of mind and i would go ps/2 as well. i'm not too keen on usb for keyboards but i have used them when i must.

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it seems like you wantend almost an all or nothing type fix. i think we covered all the options so unless you have some more questions about what i suggested i think i'm pretty much done here.

 

[Typhoon859]

from what i've read adding a seperate IRQ for a usb connected keyboard can be a rather bad thing.

this is why i suggested possibly using a pci usb card which *might* have its own IRQ but i'm not so sure.

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truthfully i dont think it will be much of a hardware problem and is mostly just a psychological "but i know its there and it really bothers me" problem. sort of like having a large hole in the floor under your kitchen cabinets. it doesnt affect anything for the most part but it can still drive you nuts. sometimes we just want it fixed for peace of mind.

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reaction time to audio and visual stimulus is going to be similar. my only point was that its pretty much impossible to get closer to the target mark then your reaction speed and that 5ms isnt really going to matter either way.

yes, i realize its more piece of mind and i would go ps/2 as well. i'm not too keen on usb for keyboards but i have used them when i must.

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it seems like you wantend almost an all or nothing type fix. i think we covered all the options so unless you have some more questions about what i suggested i think i'm pretty much done here.

Yep, everything was covered, thanks. Perhaps somebody might have an inventive idea but in terms of what actually exists, I think that's pretty much it. It's not an all-or-nothing solution per say that I was looking for. What would be a solution in between would you say? The best alternative to PS/2 remains to be USB, lol; it's not like there's something that somehow otherwise solved the inconsistency problem that's possible with USB, and I'd obviously be fine with that. Basically, the solution would need to focus on a function similar to that of a hardware interrupt as it's done by PS/2, if a PS/2 solution can't be integrated. I wouldn't really say that's all or nothing as much as actually being a solution to the root problem, not even to mention my situation.

Just to address the response time thing again, the point is, it's not about response time; it's about perceivable difference, and we can consciously perceive differences of even as little as 10 ms in sound. In a musical context, it makes a difference, even if you're not aware it's happening. Even more so in terms of how sounds interacts with other sounds in such small time disparities. Ideally, it would be 0 ms I'm after but that doesn't even happen in the analog domain, lol (though obviously, it's much closer, and otherwise, as ideal as it gets).

 

[heymanj]

from what i've read adding a seperate IRQ for a usb connected keyboard can be a rather bad thing.

this is why i suggested possibly using a pci usb card which *might* have its own IRQ but i'm not so sure.

---

truthfully i dont think it will be much of a hardware problem and is mostly just a psychological "but i know its there and it really bothers me" problem. sort of like having a large hole in the floor under your kitchen cabinets. it doesnt affect anything for the most part but it can still drive you nuts. sometimes we just want it fixed for peace of mind.

---

reaction time to audio and visual stimulus is going to be similar. my only point was that its pretty much impossible to get closer to the target mark then your reaction speed and that 5ms isnt really going to matter either way.

yes, i realize its more piece of mind and i would go ps/2 as well. i'm not too keen on usb for keyboards but i have used them when i must.

---

it seems like you wantend almost an all or nothing type fix. i think we covered all the options so unless you have some more questions about what i suggested i think i'm pretty much done here.

Yep, everything was covered, thanks. Perhaps somebody might have an inventive idea but in terms of what actually exists, I think that's pretty much it. It's not an all-or-nothing solution per say that I was looking for. What would be a solution in between would you say? The best alternative to PS/2 remains to be USB, lol; it's not like there's something that somehow otherwise solved the inconsistency problem that's possible with USB, and I'd obviously be fine with that. Basically, the solution would need to focus on a function similar to that of a hardware interrupt as it's done by PS/2, if a PS/2 solution can't be integrated. I wouldn't really say that's all or nothing as much as actually being a solution to the root problem, not even to mention my situation.

Just to address the response time thing again, the point is, it's not about response time; it's about perceivable difference, and we can consciously perceive differences of even as little as 10 ms in sound. In a musical context, it makes a difference, even if you're not aware it's happening. Even more so in terms of how sounds interacts with other sounds in such small time disparities. Ideally, it would be 0 ms I'm after but that doesn't even happen in the analog domain, lol (though obviously, it's much closer, and otherwise, as ideal as it gets).

I have and old keyboard that is top notch (Keytronic FlexPro) - it has an AT style connector (5pin) which I've added an adapter to so that it can now work successfully with PS/2 style connectors. New computer at the office, a Lenovo c30, which only has USB support. I purchased a PS/2 -> USB converter that appears to work quite well - except when I reboot the system. Upon reboot, the FlexPro keyboard is not recognized - in fact I get the message that no keyboard is attached.

Is it safe to assume that this is really a timing issue, and is there anyway to resolve this, short of my current solution which is to boot w/USB keyboard and then swap it out with my FlexPro?

jerry

 

[Typhoon859]

Hey there! It looks like the answer to my question would also answer yours in a way. I can say however that when looking into this, I've seen discussion about that and I think there are in fact some USB -> PS/2 adapters which function in a way that they are actually recognized by the motherboard as a keyboard input device. For that, a solution I think is certainly available (although I'm not sure if the additional PS/2 adapter you have for the keyboard might interfere in some way) but there would be much better places than this thread to look into the matter. I'm sure there are plenty of other threads specifically on this issue actually.

Good luck!