Looking for Larger Alphanumeric Display

Discussion about my Wifi Radio project at http://mightyohm.com/wifiradio/ or my WL-520gU talk at NOTACON.
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LloydEwing
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Joined: Sun Feb 21, 2010 4:47 pm
Location: Austin Texas U.S.A.

Looking for Larger Alphanumeric Display

Post by LloydEwing »

I would like to build a version of the MightyOhm radio in a larger box to match the style of the typical AM/FM receiver. I really want an alphanumeric display that is large enough to read from across the room, since most of the internet radio stations I listen to do not announce the track that is being played.

Most of the LCD displays I find in the catalogs have characters that are about 1/4 inch high. Displays larger than that (that would be practical for this purpose) seem to be more expensive than the combined cost of the rest of the project.

I would be happy with a single-line LCD display and a minimum of around 25 or 30 characters. It will help a lot if it can scroll horizontally pixel-by-pixel instead of a character at a time.


I was considering other options if I cannot get the larger LCD display I want:

An LCD photo frame would be ideal, but I haven't seen them mentioned on this message board recently. I assume that connecting the photo frame interface to the WL-523gU is a tough problem or someone would have done it already.

Another possibility would be to use the LCD display from a consumer product such as an old camcorder. Presumably that would require an ASCII-to-video converter. IC's for that purpose should be readily available. Could someone suggest where I might find information on ASCII-to-video circuits?

I also wonder if it would be practical to use a small LCD display from an old laptop computer. If the LCD's have something resembling a VGA interface, then an ASCII-to-VGA converter could probably be used.


Thanks for any suggestions,
Lloyd
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mightyohm
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Re: Looking for Larger Alphanumeric Display

Post by mightyohm »

Converting ASCII to a signal that can drive a laptop LCD sounds challenging. I don't know of a straightforward way to do this, but it's possible that others have already done it. It might be cheaper and easier to find an old laptop and use that as the Wifi Radio instead!

Maybe something like this could work?
http://www.sureelectronics.net/goods.php?id=903
jeroen94704
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Re: Looking for Larger Alphanumeric Display

Post by jeroen94704 »

If I ever get around to it, my plan is to use a photoframe as a full-color, hi-res display for my mpd box (which is based on a WL-500G router), showing things like album art etc.

Physically connecting a display isn't hard at all, since many of these frames can be used as secondary monitors through USB. So no fancy hardware hacking and/or soldering is necessary. The problem is driving the display. There are no drivers or anything available. For the Samsung photoframe I have, I need to draw everything manually in memory, encode it as a jpeg, and send that over the USB line. This isn't necessarily rocket-science either, but it IS a lot of work. Oh, and it remains to be seen if the routers we use have the CPU power to do all this at reasonable speeds, while playing music stutter-free.

Jeroen
LloydEwing
Posts: 11
Joined: Sun Feb 21, 2010 4:47 pm
Location: Austin Texas U.S.A.

Re: Looking for Larger Alphanumeric Display

Post by LloydEwing »

Jeff,
The Sure Electronics LED looks like it might work. But when you add up eight of those boards (to get 32 characters) and the "demo driver board", the total comes to around $75. Then after it is all assembled, it is not clear exactly what capabilities the display would have. (For example, how would it interface to the WL-520gU, and would it have the ability to scroll horizontally.) I really like working with components that have been manufactured as commercial products so I can be sure that their basic functions don't have bugs and they are well documented. I hesitate to try to build a larger project using a lot of components that appear to be prototype boards built in small quantities for the hobby market. I am afraid that the display could turn into the largest part of the project.

This question might more appropriate in some other forum that deals with displays for use with microcontrollers or embedded systems. I didn't find anything like that, but let me know if you have any suggestions.

Thanks,
Lloyd
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