Scrolling a 5X7 LED display

Jonathan

Hi All,

I am using an LPT2657AA 5X7 led matrix display, driving it with a MAX6953. The MAX driver has a built in font set, and an I2C interface. I managed to get the whole thing wired up and displaying the built in font set. I haven't messed with using the bicolor aspect yet, just one color to get things rolling.

So, my question is, how the heck do I scroll letters across the display? I currently have 2 displays so I have a width of ten colums. How on earth do I take a string like "Parallax Rules!" and scroll that across the displays? Someone must have made a scrolling sign with a Stamp before. I can tell this is one I'm unlikely to figure out on my own, so I'm snooping around for an example to work from.

Thanks for any input!

Jonathan

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www.madlabs.info - Home of the Hydrogen Fuel Cell Robot

Brian Carpenter

i have the same chip and a very unique app.· would you be willing to share your code on making the Basic stamp talk with the 6953?

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It's Only A Stupid Question If You Have Not Googled It First!!

Jon Williams

If the chip has a built-in font then you may not be able to get it to scroll smoothly; what you need is individual column control so that you can "paint" characters on screen where they need to be. On our web site you'll find a Robo-lympics badge that has a scrolling display. The driver code is in SX/B, so you should be able to follow it and you may glean something useful for your project.

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Jon Williams
Applications Engineer, Parallax

Bean

Only a company like Parallax would make a product, then "give away" the schematic and source code.
Here is a link to it http://www.parallax.com/detail.asp?product_id=28099
The source code link is at the bottom of the page.

I have one of these and they are cool. You need to have the SX-Key to change the message though.
Bean.

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"SX-Video·Module" Now available from Parallax for only $28.95

http://www.parallax.com/detail.asp?product_id=30012
Product web site: www.sxvm.com
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Those that would give up freedom for security will have neither.
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Jonathan

Hi Everybody,

This post dates back before I got the code working. I do have working code posted in another thread. I'm not at home so I can't re-attach it here. It's only set up to do 2 digits, but can easily be expanded for 4. As Jon noted, the built in font is of no use, so I made a variable width font that looks nice, also in the code attachec in the other thread.

If you can't find it, drop me a line.

BTW, the code *requires* a 2p or higher that supports I2C and STORE.

Jonathan

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www.madlabs.info - Home of the Hydrogen Fuel Cell Robot