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Hello, Guys. Again , thank You for answers.
Yes,
How I can see it is no point to works with LC7981(LCD controller).
For beginner like me, probably I need some more advice:
-which avr xmega interface (board) for controlling LCD (virtual in PC )
With USB and parallel port can I use for this project(links or full item name will be
Helpfull )
And
-which connectors have to read (obtain) from MCU.
I know data bus(D0-D7) , CS/, R/W and which more? To
Connect to xmega interface or o'scope?
Marek
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Most any of the Mega chips would probably work. The Tiny stuff won't likely have enough pins so you could probably skip it. I've been working with the Mega128 recently on a project and find it to be fast enough with plenty of memory for my needs. And I am driving an LCD with it that has the HD44780 controller chip using just the half addressing (to keep pin count down) while also reading a serial data stream at 250 kbps and pulse-width-modulating an output at a 10 us duty-cycle. All while clocking the chip at just 16Mhz. (It goes to 20Mhz)
You will need a programmer and Atmel Studio 6. The software is available on their web site for free. You can save some money by purchasing the STK500 programmer (which will program the Mega128) or you can find a third-party programmer that implements ISP (In System Programming). And buy a few chips... they are cheap and you'll likely lock yourself out of at-least one. Everybody does at some time or another. 
I think that you could probably have good success with this chip. You would need to identify the pins on the LC7981 that are connected to the microcontroller and figure out which is which. The good thing is that the LC7981 will only be connected to two things; the microprocessor and the LCD, so figuring out what is what should be pretty easy with the manual for that chip.
You *should* be able to set the pins on the AVR to high-impedence input mode and be able to pick-off the signals in-circuit... at least while you are testing and debugging. For a permanent install I would suggest desoldering the LC7981 and wire-up the pins on the Mega128 in its place. This is where a logic analyzer will be a big help. You'll need an acquisition rate at least twice the clock rate of the CPU in the device (likely 8Mhz but you may have to decode the information on a crystal to know for sure.) The analyzer will let you see the electrical signals as they happen in-circuit. The manual for the LC7981 chip should address the timing sequences for the pins which you should be able to verify with a logic analyzer. The manual will also talk about the initialization sequence and what, specifically, the chip will do for the different command modes. All this has to be provided so the guys writing the software on the micro side know how to drive the controller chip properly. The LCD controllers don't take serial commands... it is all at the bit level and driven by the clock... very low-level. But the manual for the LC7981 will cover all of that. Your task would be to write code for a Mega that would emulate this behavior. If I were attacking this I would likely figure out a way to execute an ISR (interrupt service routine) on the CS line. When the Mega sees this go high or low (depending on which is the 'valid' state), then the Mega can read/decode the data lines. Making it interrupt driven would be the way to go in my opinion.
There are some libraries out there for the Mega's that will drive various LCD controller chips. Looking at some of them might help you understand that side of the equation. You might also read up on http://avrfreaks.net and post some questions there. Note that the people there don't suffer poorly asked questions very well. You should make sure you have a well thought out and to the point question before you post over there.
There are also a lot of tutorials on sending serial data from an AVR chip to a PC. You will need that to send the data from the Mega to the PC. If I were you, I would probably try to keep this simple. Assuming the LC7981 works like most other controllers, the micro will load a character at a time onto the interface and clock it into the display controller. There are also control codes to clear the display, move the cursor, etc. I would turn those into similar control characters that could be send over the serial link while passing alpha characters as-is. If you do it this way, you could 'debug' the PC side of things using just hyperterm or something like that to read the stream of characters coming in. If the letters, numbers, and control characters are transmitted to the PC as they arrive at the AVR, you can pretty it all up in an app later.
You might also check and see if you have a hacker-space in your area. You can probably find someone there like me that knows the AVR stuff and might want to take this on as a project with you. This is the kind of novel project that guys like me are always looking for to take on as a personal project... out of the mainstream and yet very intriguing. I think the idea is cool and I could actually see something like this being useful beyond your project.
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Hi,
I have a Booteable USB device, from which i booted my System.
But the HDD connected to the Base board(Mother Board) is not detected on USB Boot up.
How to make hdd to be detecteable on USB bootup.
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There's really no good reason this drive isn't being detected. It's probably a safety feature of the computer since booting off CD or USB is an easy way to get to the files in the HDD. Look through the BIOS settings as already recommended.
It may also be possible that your booted OS doesn't understand the file system of the HDD OS. This would only be a problem if they're different operating systems. If it can't understand the file system, it probably wouldn't attempt to mount it since you can do permanent damage mounting a drive with an incompatible file system.
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I tried with Bios configurations,but it's of no use. I am using QuanMax Baseboard, There is no such feature available in it,.
So I tried to make HDD as External one by using SATA to USB convertors, It works but not as expected.
GRUB Cannot able to Detect the Hard Disk even after the Successful Installation of an Operating System.
Any other way to fix it.
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SrivathsanRaghavan wrote: GRUB Cannot able to Detect the Hard Disk even after the Successful Installation of an Operating System.
Not sure I follow what you're saying here...
What OS are you using anyway?
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I have Installed and Booted Debian 6 on/from USB Device.
I have a new HDD, On which the operating System in USB should be copied.
Since the Operating System in USB is Linux, It is possible to copy the entire file system from one booteable media to another, I have tried this with two HDD's and made it work.
But when i try to copy file system from USB to HDD, I can't able to detect HDD on boot and manually.
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SrivathsanRaghavan wrote: But when i try to copy file system from USB to HDD, I can't able to detect HDD on boot and manually.
You mean after the copy? ...or because it wasn't mounted so you can't do the copy in the first place?
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HDD wasn't mounted, So I can't able to copy file system from USB
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Typically you can manually mount a hard drive if you can find it. Off the top of my head, I can't remember how you go about mounting a hard drive to a logical drive (look up the mount command, also, Linux has a fairly straight forward drive naming convention so you may be able to easily mount it).
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The device usually has to have a "B" USB port on it making it a node (rather than a hub, which provides power). I have not seen a Win 8 device designed to be a node. It is always the root hub and so seems to always be equipped with the "A" port. I don't think the USB specs allow the consumption of power via an "A" port. So the short answer, I believe, is no.
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Wow... that is actually pretty cool. I think the battery in the keyboard is a pretty novel idea. I've got to hand it to Lenovo... that are really innovating in this area. I got one of the Intel Ultrabooks in the App Innovation contest and without fail, everyone I showed it to asked me if it was "the one that the display flips around on"? Which is, of course, the Lenovo (I had to begrudgingly admit).
I noticed the reviewer seemed down on the idea that it charged through the USB port. I can understand why... the current limit is pretty low so I imagine the the charge/discharge ratio is in negative territory (so it takes more than an hour to get an hour of runtime). I've noticed that on my Nexus 7 tablet if I plug it into a "standard" USB port... it will take 10 to 12 hours to fully charge. It needs a high-current USB port or, better yet, the high-current charger it came with. I bet that the Win 8 tab would see the same behavior.
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Hello,
It is posible to get some vga converter from 31kHz to 45kHz of any more compatibile?
Thank You
Marek
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So, I'm doing my first PC build in about 10 years, and I've never installed an after-market heatsink (the kind with the big tower, etc.). I got the tower mounted to the mb and processor fine, but for the life of me, I can't figure out how to attach the fan to the tower. The fan has two arrows at the top that are at right angles, and the fan is supposed to be mounted by two (or four?) high-tension wire clips that slip into the fins on the tower. The instructions are absurdly awful with no clear diagrams. I can't even tell which way the fan is supposed to point, much less how to mount it.
It's a ThermalRight True Spirit 140 ([^]); any tips on installing?
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Well the picture in your link shows the fan held on by a couple of wire clips. If they didn't ship, I don't know what you can do. You might be able to just tie it down with a bit of hard foam or something to cushion it. Millimetre-perfect location is not important. You should be able to figure which way round from the curve of the blades in the pic.
wrt the arrows: One shows which way the blades move, the other shows which way the air moves.
Cheers,
Peter
Software rusts. Simon Stephenson, ca 1994. So does this signature. me, 2012
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Thanks; I was able to figure it out from the pictures the next day. Those clips were included but were an absolute beast to install. I'm not sure why they think they have to be that tight, but that easily took up half of my total hardware installation time.
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Way back when I worked in speech recognition Andrea noie cancelling mics were the best. Make sure to have the mic off to the side of your mouth, you dont need to shout directly into it, and if you arent breathing all over it it will understand you better.
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I had a problem with my laptop, when i started it, it showed a blue screen and then could not start normally except through safe mode. It is slow and has lost volume. What could be the problem and how do i solve it?
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Unfortunately it's impossible to guess what may be wrong. It could be a hardware or a software problem. I would suggest you try a computer repair shop if there is one in your area.
One of these days I'm going to think of a really clever signature.
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do you have any suggestion of what i can do
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Only what I already suggested. From the information you have provided it is impossible to offer anything more.
One of these days I'm going to think of a really clever signature.
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hi,
1 - setup new windows, i hope it will work 
2 - if didn't then follow my instructions:
> open the back cover for RAM , and remove them all then clean the place for them , and clean them "the copier place of the RAM ".
> connect the RAM or one by one if there is more than One RAM and each time try to start your laptop.
> if didn't work change the BIOS battery .
> if not then make sure that the FAN of your processor is working good and it's clean.
i hope this steps will solve the problem 
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1. Why are you telling me this?
2. What evidence do you have that any of this will address OP's problems?
One of these days I'm going to think of a really clever signature.
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