What type of HMI touchscreen do I need?

Hi,

I am looking for a LCD type touchscreen. this touchscreen would be about 10 inches. What I want to design on this touchscreen is a virtual keyboard that is custom designed with certain keys not on the standard QWERTY keyboard.

I know there are lots of touchscreens out there that allow design of the layout. However, I need to OUTPUT these key strokes via a USB port that will go to ... WHAT ?

I need this to run on a tablet PC which already has the virtual keyboard. How do I make the keystrokes output via the USB, and be understandable to the controller. The controller is a simple computer. This simple computer is a CNC mill.

So, what I am trying to do is remove the exisiting keyboard that is broke. There is not a replacement available any longer. I did not like the keyboard anyway from a layout standpoint. So, I want to take a tablet PC and attach it to the 4 wire input of this CNC mill so I can have a virtual keyboard on my PC tablet.

I would think there is a API that can handle the virtual keyboard output to USB, but what do I need to attach to the USB to get a 4 wire signal? Maybe a USB > Serial port adapter? I have 3 of those today already. IOGear is the best on i have used so far.

Any ideas on this please...

Basically, what you need is a small, tablet PC.

You write a program on that tablet PC that creates a custom, full-screen keyboard.

Now, the question is: How did the old keyboard connect to the PC on the CNC mill? Was it also custom? Was it a normal keyboard with fancy labled keys so when you pushed the "Cycle Start" key, it sent a letter "R" to the computer?

What is the computer controlling the CNC mill running? Windows or some other OS?

I see you having a couple options.

HI,

Thank you for helping me with this.

I already have the Tablet PC. it is the Motion Computing model. I have 3 of them actually. I have installed Windows 7 on one of them. The keyboard is so much better on W7 than XP tablet edition.

The keyboard is connected with flat ribbon cable. I will figure out what signals travel over this ribbon cable, but I want to make sure that even getting a Tablet PC or any HMI device to output keyboard strokes is doable. I am 98% sure that it is standard keyboard scan codes. I have read that a keyboard is a microprocessor 8042 that gets its power from the motherboard and scans for key press events, then outputs code like on this webpage http://www.computer-engineering.org/...cancodes2.html

I have not been able to come across any postings on various forums where someone wanted to OUTPUT keystrokes via the USB, or even a common serial port.

Any help and direction is appreciated.

It's a rarity. You need something like this: http://www.centrillium-it.com/Products/UsbDE/
for that part.

Well, let me throw another application I see with this same method.

I just purchased a Wacom Intuos 4 tablet for my desktop PC. The reason I got the Wacom is that I love my Tablet PC virtual keyboard and INK to text, and my MasterCam program can work with the tablet PC pen also. Now, I hate the Wacom ink to text because you cannot see what you are really writing on the tablet, only up on the screen. If you notice when you write on paper, your eyes follow the pen and writing you are leaving behind. Same with a Tablet PC. you can see the text and ink right there under the stylus. However on the Wacom tablet you cannot. it looks alot more shaken and poor trying to look up at the PC screen while writing on the tablet. NOW, if you can get a nice Tablet PC to be the writing tablet for the desktop PC also, this would get ink to text, or even ink forums going alot faster in the public. Here is a ink to forum and it really is creative. http://www.gottabemobile.com/forum/f...s.asp?TID=6275

So this thought all came to me with my CNC Mill having issues with the keyboard, and getting the tablet PC to DNC my programs... the keyboard is an interface device. Surely my Tablet PC can output these virtual keyboard commands. Then, well, why can't I plug my Tablet PC into my Desktop PC via USB and use my tablet PC like my Wacom tablet?