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USB vs PS/2 vs COM vs LPT
AndyWarne:
--- Quote from: Driver-Man on September 20, 2010, 11:17:01 am ---
--- Quote from: severdhed on September 20, 2010, 10:32:27 am ---what is the point of this discussion at all? is there anyone here using a USB interface that has ever had lag problems with their controls? I have been used several different USB interfaces and have never once noticed any kind of performance issue, even when using multiple usb interfaces simultaneously.
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The point I am interested in is to find out the real numbers, the frequencies at which these ports and controllers operate, maybe that's all fine after all, I have no source to confirm either way and I'm lazy to test, but what I do know is that this interface simply can not have any of those problems, it's perfect!
The points you might be interested in, besides being cheap, fast and perfect, is that even though you may not notice.... if you fail to jump over barrel in Donkey Kong you would know it is only you to blame, and not Windows or some keyboard controller for reporting your jump one frame too late. In other words, it would make the game more "legitimate" and probably easier too. You would not want to be failing to break some high-score just because you can run the game at only 12 FPS, right? This would be almost exactly the same, just need to find out how bad or not bad it really is. -- Don't forget that USB can be set up to probably 1000Hz, so perhaps your friendly neighborhood Driver-Man can solve the problems if it turns out there are any. My name is not Driver-Man becasue I drive a truck, but becasue I make drivers.
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Another factor is unpredictable delays caused by sharing of interrupts. The parallel ports interrupts are shared with other items such as sound card, network card etc. The PS/2 port on modern motherboards is shared with the ACPI interface but I would suspect the effect of that share is far less than a network or sound card.
CheffoJeffo:
--- Quote from: Driver-Man on September 20, 2010, 10:06:00 pm ---I know exactly what happens, take a look at the driver source code.
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This is one of the reasons that you are seen by many to be a troll ... you evade even the most obvious and direct questions.
Why don't you post what happens ?
Answer the question, Claire!
SavannahLion:
Is it fair to point out, once again, that arguing about the parallel port and its "superiority" over the USB or even the PS/2 port is a moot point?
--- Quote from: Driver-Man on September 20, 2010, 08:45:02 am ---
--- Quote from: SavannahLion ---USB is the most popular because that is what dominates the peripheral interface. So, for most of us, the decision is already made.
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Ok, and it is probably difficult to notice the difference with most of the games. However, with 2 player simultaneous games, especially those where timing is critical, such as Street Fighter series, this could make a difference between executing some combo easy and not being able to pull it off at all. -- Did I mention there need to be scan codes sent when key is both pressed and depressed, which makes it "double-trouble" for keyboard controllers, if that turns out to be the bottleneck.
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You have completely missed the point there. For many the decision has already been made. No parallel port, period.
--- Quote from: patrickl on September 20, 2010, 08:26:21 am ---Yeah he's bound to come down hard on SavannahLion for claiming that PC's without a PS/2 port exist.
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Then he's more than welcome to take a look at mine.
Driver-Man:
--- Quote from: AndyWarne ---Another factor is unpredictable delays caused by sharing of interrupts.
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No interrupts here, you can handle LPT directly whenever your please and as often as your CPU can tick. You can also read the state repeatedly while waiting for vertical retrace.
If you are talking about the driver that would output keystrokes, for use with say DOS games, then you simply stick the routine to the timer interrupt. This is how I made my DOS TSR, and good thing about it is that you can program the timer and set whatever resolution (frequency) you want.
--- Quote from: CheffoJeffo ---This is one of the reasons that you are seen by many to be a troll ... you evade even the most obvious and direct questions.
Why don't you post what happens ?
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That was not direct question, but rhetoric question with wrong assumption, like asking: "Does your mother know you're gay?", having that you're actually not. Anyway, I did explain what really happens, here it is again... there is a loop that sends signal to each separate "ground wire" for joysticks 1 to 7, in sequence. Inside that loop you simply check if the signal has passed through any of the 9 data lines, and whichever line is set it means the microswitch circuit was closed, that's all.
Can you define "troll" in relation to my "evil intentions"? What is it do you think I am doing? Is there anything I want or need from anyone here? Am I trying to sell you anything, or take anything from you? You think I want you to fry your computer?
All I am asking is to establish the numbers, actual HARDWARE SPECIFICATION, so anyone who wants can make their conclusions for themselves. I do also offer to explain what those numbers mean and what kind of impact they can have on game play. Then I offer to fix the problems if it turns out default numbers are too low. I also told you about the perfect interface, and I am not asking for anything in return... I'm your friend, sober up!
--- Quote from: SavannahLion ---Is it fair to point out, once again, that arguing about the parallel port and its "superiority" over the USB or even the PS/2 port is a moot point?
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Playing game = "controlling your game character". Is there anything more important about playing a game than playing a game? -- It is equally bad running game below 100% and not being able to report all the input for every frame. In both cases your ability to "control" has decreased resolution and can have dire consequences on the game play, it makes the game harder and less authentic.
--- Quote ---You have completely missed the point there. For many the decision has already been made. No parallel port, period.
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You could just as well say your PC came with LCD monitor so the decision was made and you MUST use it. Do what you please and let others think and choose for themselves. Perhaps it wouldn't be unwise if you at least realize PS/2 is actually better than USB, eh?
I expected people here would be perfectionist in relation to their hardware and all the aspects of emulation, just as is MAME aspiration, but if two keys per frame is "good enough" for you, then cool... enjoy!
RandyT:
--- Quote from: Driver-Man on September 21, 2010, 04:38:03 pm ---All I am asking is to establish the numbers, actual HARDWARE SPECIFICATION, so anyone who wants can make their conclusions for themselves. I do also offer to explain what those numbers mean and what kind of impact they can have on game play. Then I offer to fix the problems if it turns out default numbers are too low. I also told you about the perfect interface, and I am not asking for anything in return... I'm your friend, sober up!
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If you want to "fix" the issue I showed you, you can't do it in software. You need to use those diodes. There's a reason they are there, and the mere fact that you don't understand what that reason is, doesn't negate their necessity. What you are telling people is wrong, and that means you really aren't being their "friend". Just the opposite, in fact.
If you want to be a "friend" to the community, make a balls level driver for Windows 2K/XP/7 that will take gamepad, LPT, semifore, morse code, whatever, and allow one to map either gamepad or keyboard characters to it and make it work under everything, regardless as to whether the input scheme is DirectInput or RAW. I doubt you are up to the task, but it's worth a shot. Otherwise, you are offering pretty much nothing other than other peoples ideas (and ruining them, by making your own changes) and attempting to call into doubt long tried and tested methodologies.
Meh.
RandyT