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How are the mouse keyboard and screen cables built up?
And what is the output of them?
If I for example press K on the keyboard, what happends?
The PROgrammer Niklas Ulvinge aka IDK
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If you press K there will be an interrupt, and the device driver will read some port data which represents a scan code. This scan code is translated to an ascii code (the current code page is used for translation).
Isn't it easy? 
Don't try it, just do it! 
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The scan code will also be dependent on the mode the keyboard is in, XT or AT.
You will actually also get 2 scan codes. The first is termed a "make code" which occurs when the key is pressed. The second is a "break code" which is sent when the key is released. In XT mode this is simply distinquished by setting the high bit of the scan code for a break code and clearing it for a make code. You then have two sets of extended keys which are "E0" and "E1" prefixed followed by one or two more scan codes to represent the key.
AT protocol is a bit different. Make codes and Break Codes I believe are prefixed instead of setting the high bits (if my memory serves me correctly). As far as I remember, Windows 9x still actually set the keyboard into XT mode so break codes and make codes were determined using the high bits (and some keyboards would send E1/E0 for a break code you'd have to do special detection, I believe that perhaps the PC98 may have done this but I don't remember, been a while since I wrote a keyboard filter).
8bc7c0ec02c0e404c0cc0680f7018827ebee
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I think my PC is slowly dying .... might be software related also...
When accessing my external firewire drive, windows tells me that the drive is not formatted.
CD and CD-R are not recognized.
any good hard-ware reporting/problem finder tool ( and how-to )?
I don't need this now, I don't want to re-install, or worse, buy another computer; the least I will do is get another hard-drive to make a backup.
Thanks.
Maximilien Lincourt
Your Head A Splode - Strong Bad
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Maximilien wrote:
any good hard-ware reporting/problem finder tool ( and how-to )?
Look Here
hope it helps 
"Go as far as you can see,and when you get there you’ll see further" - Unknown
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I'm lookng for a midrange 19" LCD Monitor, ( << €400) - what is really important?
Do I need high reaction speed (<20ms) for coding?
How much better is the image with an DVI connector? (my graphics card does it)
Any brand (dis-)recommendations? Why is Eizo so much more expensive?
How much contrast, brightness is ok?
(I have a very windowy office, but need to lower blinds anyway at brightest time of day)
Pandoras Gift #44: Hope. The one that keeps you on suffering.
aber.. "Wie gesagt, der Scheiss is' Therapie"
boost your code || Fold With Us! || sighist | doxygen
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I would, when in doubt, always go for the higher reaction ones. You DO notice slow reaction when coding, though its usually "acceptable". These times indicate the time it takes for the LCD to switch from "all black" to "all white" (or vice versa, not sure). If you want to play fast games, it is a must, if you code, you still might experience some "fogging", which can be annoying.
The image quality is better with an DVI-Connector. You have to consider, though, that LCD-panels STILL show different colors from different angles. Almost not noticeable on high-end devices, but in the print industry it still makes a difference.
I would go for Samsung or Ijiyama (Not sure if I got that name right). They are GOOD, but also quite pricey.
Eizo is "THE" company when it comes to displays (CRT and LCD). They have top-quality, excellent service and support.
As for contrast and brightness: depends. I usually use my LCD in a seperate room which has "dimmable" lights, so I can adjust my light levels to what is most comfortable. However, the display should have an even backlight distribution.
In bright light, CRTs usually are easier to read. You might ask for some LCDs to "compare" before deciding on one. Some companies still do that
Cheers
Sebastian
Cheers,
Sebastian
--
Contra vim mortem non est medicamen in hortem.
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All these things depend on what you are using the monitor for.
A high reaction speed is not the most important thing, but it should be 20ms or less because you will see the mouse cursor and many other things with a nice blur effect (can be quite funny indeed ).
A higher reaction speed is only interesting for games, especially for first-person shooters.
But take care: 20ms is not 20ms.. it depends on the monitor size. 20ms on a 17" monitor will look much faster as on a 19" only because of the size!
DVI connection normally creates a better picture, but the new monitors have very good analog inputs, too.
Another important thing is the correctness of the colors. Some monitors have big problems with colors, and that is important when you are editing images from a digital camera. There are many nice websites about TFTs, e.g. http://www.prad.de[^].
Additionally there is the question of the surface of the monitor. The light situation in your computer room is important! When the room behind you is very bright or the sun is shining at the monitor is may be better to use a rough surface to reduce reflections.
There are also monitors with a DCC/CI interface which makes it possible to setup color management and many other settings with a software, but I think this is only interesting for image editing.
Sometimes it makes sense to buy a monitor that was a demonstration model in a hardware shop because you can check it for dead pixels. Normally it takes some time till pixels turn off, and so you will have black or other colored spots on the monitor.
Take your time and read test reports to find a good monitor... have fun
Don't try it, just do it!
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Thanks for your comments - prad.de looks interesting.
The order will go out monday or tuesday, and will be delivered (or picked up by our tech), it got to be 19", and I can't try before buy
(the funs of buying on budget)
currently I'd go with the recommendation for the Acer AL1913s
Pandoras Gift #44: Hope. The one that keeps you on suffering.
aber.. "Wie gesagt, der Scheiss is' Therapie"
boost your code || Fold With Us! || sighist | doxygen
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Personally I like to look at LCD monitors, the quality of the black level (i.e. how grey is it ?) varies.
Elaine ![Rose | [Rose]](https://codeproject.freetls.fastly.net/script/Forums/Images/rose.gif)
The tigress is here 
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PLEAAAAASEEEE SOMEONE NOTICE THIS FORUM!!! 
Related to my question below, I remember getting a USB-to-PS/2 adapter one time I got a USB mouse. I'll look for it, but does anyone know if it could work with a USB keyboard? and connected to a barcode reader?
Thanks,
-- LuisR
Luis Alonso Ramos
Intelectix - Chihuahua, Mexico
Not much here: My CP Blog!
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AFAIK, these are specific to the mice they come with - they won't even work with older PS/2 mice.
[Edit: you could probably try something like this though.]
You must be careful in the forest
Broken glass and rusty nails
If you're to bring back something for us
I have bullets for sale...
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Shog9 wrote:
these are specific to the mice they come with - they won't even work with older PS/2 mice
I didn't find that adpater, so I couldn't confirm this.
Shog9 wrote:
you could probably try something like this though
I did. I stopped on Office Depot on my way to the office looking for a USB to PS/2 adapter and I couldn't find any. I bought a PS/2 to USB adapter just in case, and.... it worked!!! 
I simply plugged the PS/2 barcode reader into that adapter by itself, and I left the USB keyboard as it was; and after a restart, everything worked fine.
-- LuisR
Luis Alonso Ramos
Intelectix - Chihuahua, Mexico
Not much here: My CP Blog!
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These devices contain special wiring that tell the mouse hardware itself to emit PS/2 signals rather than USB. They don't work with anything other than the original hardware (OK, they probably also work with other mice by the same manufacturer).
Stability. What an interesting concept. -- Chris Maunder
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Hello,
A good question for this new forum! 
I have a PS/2 barcode reader I'm trying to make work with an USB keyboard. So far, what I've done is:
1. Turn on the computer with a PS/2 keyboard and the PS/2 barcode reader.
2. After Windows startup, fire up Notepad and read a barcode.
3. Disconnect the PS/2 keyboard and connect the USB keyboard.
Everything works fine.
But if I try to boot up with the USB keyboard and the PS/2 barcode reader, it won't work. It beeps the first time I read a barcode, but it's not displayed in the screen. After that, it won't read anything.
I've also tried booting up with just the barcode reader and plugging in the USB keyboard later. The keyboard works fine, but not the reader.
So, any ideas? This has driven me nuts all the morning.
-- LuisR
Luis Alonso Ramos
Intelectix - Chihuahua, Mexico
Not much here: My CP Blog!
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Here's an odd one...
A coworker brought in a relatively new Dell that would not respond in any way to pressing the On switch. I tested the switch - works great. I jumpered the PS-ON pin on the power supply to ground and it fired up perfectly. I reconnected the switch, removed all the loads (disk drives, unnecessary expansion cards, RAM, etc) and tried again - no response. I measured the voltage at the PS-ON connection to the MB while pressing the ON switch - no change. I reported all the symptoms to Dell, having decided the the MB has a problem, and they agreed. A replacement MB and power supply were shipped and installed. The same problem continues.
Am I missing something obvious, or is this box infected with gremlins?
"...putting all your eggs in one basket along with your bowling ball and gym clothes only gets you scrambled eggs and an extra laundry day... " - Jeffry J. Brickley
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Roger Wright wrote:
Am I missing something obvious, or is this box infected with gremlins?
Did you check for continuity in the wires going from the connector to the switch? Also, have you inspected the connector to verify that the little prongs are making contact with the pins on the MB? Probably really hard to do though.
Marc
My website
Latest Articles:
Undo/Redo Buffer
Memento Design Pattern
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Marc Clifton wrote:
Probably really hard to do though.
Yup! With what I have available, impossible. What I might try, though, when he brings the box back in, is shorting the pins on the motherboard that the switch should connect to. I can get on those - should have thought of it earlier...
"...putting all your eggs in one basket along with your bowling ball and gym clothes only gets you scrambled eggs and an extra laundry day... " - Jeffry J. Brickley
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Roger Wright wrote:
I measured the voltage at the PS-ON connection to the MB while pressing the ON switch - no change
Does this mean when you press the power on switch the voltage on the switch line (measured on the motherboard) doesn't drop to ground ?
It would be as simple as a dodgy connection and when it's at the angle to fit onto the motherboard the conenction is bad.
Oh the joys on intermittent connections
The tigress is here
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That could be, but there was no way to get on the switch connection other than the connector itself. At the MB end of the switch connection, the signal drops to ground correctly, but at the PS-ON connection to the power supply there is no response. I also removed the switch connector and manually shorted the pins with a paper clip - no response.
From the results of this I decided that the MB is probably bad, and contacted Dell support. They walked me through several other steps, then told me that the MB was probably bad. My buddy ordered a new MB and the power supply, then installed them himself. No joy. Ah well, can't win them all, I guess.
"...putting all your eggs in one basket along with your bowling ball and gym clothes only gets you scrambled eggs and an extra laundry day... " - Jeffry J. Brickley
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We did have a computer here that wouldn't start at all. Very puzzling. No heatsink on the processor (we were building it from bits, and wanted to make sure it worked, and were planning to turn it off straight away, so assumed we could do without the heatsink for testing).
Then we put the heatsink on the processor, and it worked.
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Now that's just plain weird! It should have at least started, then fried in the first 30 seconds.
"...putting all your eggs in one basket along with your bowling ball and gym clothes only gets you scrambled eggs and an extra laundry day... " - Jeffry J. Brickley
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Now this time, really.
What's the difference between the two? Why are there two?
Pandoras Gift #44: Hope. The one that keeps you on suffering.
aber.. "Wie gesagt, der Scheiss is' Therapie"
boost your code || Fold With Us! || sighist | doxygen
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Socket 939 supports dual-channel RAM, while socket 754 allows only a single memory channel.
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