IBM 4820 touch screen

**Sly1990** · 09-04-2006, 12:52 PM

I didnt tried a VGA DB15 conversion yet. I'm unsure if it will be possible since the IBM Manual says it uses DVI-D Video.

I've ran it on an old IBM 4MB Office desktop Videocard (DVI Connection Only) or on my actual VideoCard (MSI FX5900XT) with the DFP-to-DVI cable I got with the monitor..

The exact model is 4820-48T. (Capacitive - USB hub - DVI Color)

Connection Pinout for the USB/TouchScreen

IBM RS485 --- USB Port
Pin 1 --------- Pin 1 (Red +5V)
Pin 2 --------- Pin 2 (White D-)
Pin 3 --------- Pin 3 (Green D+)
Pin 4 --------- Pin 4 (Black GND)

Optionnal Power source input (RS485)
Pin 5 - GND
Pin 6 - 12VDC 2A

*Usefull when doing a permanent install

**gmctavish** · 11-26-2006, 01:47 PM

Originally Posted by lez

Just worked out the pinouts and posted them on the uk site, you can find them their.

Lez - I'm about to purchase at 4820-4FT 12.1" monitor and you seem to be the world's leading expert on getting one of these things connected to a computer. I've read your posts and done a bunch of similar research to you but still have a few questions.

First, you reference the pinout that you posted to the UK site... which uk site? Do you have the web address? Also, you mentioned that you weren't going to be installing your touch screen into your new car - any interest in selling the cables and power brick that you have?

Finally, the reason for the 8 pin RS232 connector (which I'm sure you know now) is to support the magnetic strip reader and the touch screen at the same time.

Please get back to me - I very much appreciate any help you can provide.

Thanks!!

Gavin

**lez** · 11-26-2006, 02:21 PM

Hi.

Yeah I noticed the magstripe adaption, I take it you have the same dumb silly connector for serial as I have........

http://www.digital-car.co.uk/forum/s...ead.php?t=4584

**gmctavish** · 11-26-2006, 02:28 PM

I do have the same rediculous serial port connection. I am baffled by IBM's decision to have the connections be completely proprietary. I've found a company selling the video cable, but I haven't been able to reach them to determine what that will cost me. I haven't been able to find anyone selling the serial cable yet - but I'm still looking.

I'm very excited to get this monitor up and running - but from your posts - its going to be a pain.

You're not, by any chance, looking to sell your cables are you?

Any other tips or advice before I embark on this construction project?

**lez** · 11-26-2006, 03:10 PM

I did not get any cables, I built some, its really easy to build cables, finding out where the wires go is always the problem, and thanks to me(!) thats been done, its on the web site.

Dont bother trying to buy plugs for monitor end, just buy a 9 pin and solder 3 wires from it (about 30cm in lenght) to the screen, do the same with a 15pin for the vga, pass them through a hole in the case back, then you can connect these 'pigtails' to a standard set of cables.

**gmctavish** · 11-26-2006, 03:11 PM

and believe me - I'm happy for your post!

I'm going to purchase this monitor then and go get the connectors this week - I'll let you know how it goes. Thanks for your help so far.

**lez** · 11-26-2006, 03:40 PM

Anyhelp I can give I will, still little busy at the moment with life and also my other projects, which are currently stalled as I'm having PCB issues, cant get toner transfer method to work too well, so resurrected and also bought a plotter (ebay!), spent last 3 days trying to build a good working pen to draw the etch resists, all just seems to come off when etching. been a bad week really, lots of wasted boards.

**Rayman411** · 12-30-2006, 05:45 PM

Regarding the pinouts on the 4820 end, how are you numbering the connections? I'm sorry if this is a dumb question, but I had to look up the pinout diagrams for the serial cable and VGA standard. I'm not great with electronics but I've been soldering kits and car audio for 3 years now, just havn't worked with making custom cables. ANY help would be greatly appreciated

**jaspr180** · 01-17-2007, 01:35 PM

Originally Posted by lez

I did not get any cables, I built some, its really easy to build cables, finding out where the wires go is always the problem, and thanks to me(!) thats been done, its on the web site.

Dont bother trying to buy plugs for monitor end, just buy a 9 pin and solder 3 wires from it (about 30cm in lenght) to the screen, do the same with a 15pin for the vga, pass them through a hole in the case back, then you can connect these 'pigtails' to a standard set of cables.

Lez,

I would like to attempt this project as the 4820-4ft's are pretty cheap. I am going to use mine as a controller of a HTPC. Am I understanding that you are soldering your cables directly to the 4820? I would prefer to just connect a few different serial/vga cables together to form a detachable cable if needed. If I am wrong about this assumption I am sorry. Are you only using 1 VGA(15pin) and 1 serial(9pin) to complete this, or are there extra connectors needed? I can figure out the pin configuration but I dont understand since there are 2 cables (video, touchscreen) coming from the 4820 and there should be two goign to the pc correct?

**lez** · 01-22-2007, 06:09 AM

Originally Posted by jaspr180

Lez,
I dont understand since there are 2 cables (video, touchscreen) coming from the 4820 and there should be two goign to the pc correct?

I had 2 sockets on the 4820 to connect to the two sockets on the pc, in an ideal world I would need 4 plugs and pieces of cable.

however, not being an ideal world, I could only find 2 plugs, for the pc, I could not find a supplier local to me for the 2 plugs to fit the 4820, so I just soldered the cables into the 4820.

I would have liked to have done it in a more professional manner, but I had no plugs.

cable pinout above, oh hang on its not above is it, is on the 'other site' from the uk, any how cable pin out is done, it took me /ages/ to get the wiring sorted for the serial side of the TS.