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My first Erco-style ebay find — Parallax Forums

My first Erco-style ebay find

Jeff HaasJeff Haas Posts: 421
in General Discussion
I wasn't tempted by the cheap powerbank, but I was looking for a display to show numbers. It seems that 8-digit, 7-segment MAX 7219 modules are currently...$1.55 shipped (that's $2.12 for you Canadians)!

MAX7219 8-digit display

I only bought one. They'll probably be $0.99 next time I want one.

Comments

  • hatallicahatallica Posts: 175
    What? You don't have a few extra HC4LED modules sitting around?

    A few years ago, a surplus shop was unloading some LED modules with PT6961 controller (presumably a manufacturing goof, as the LED colors differed from the description).

    I probably have 15 LED display modules of various flavors ... and no active projects that require one. Having admitted my hoarding problem, I am a step closer to resisting this one.
  • Hal AlbachHal Albach Posts: 747
    I ordered three several weeks ago. The only down side is the really long shipping times. Supposedly I going to see my order sometime the first week in March.
  • ercoerco Posts: 20,256
    Good find, Jeff. You DID buy many more than you needed, right? Often times you can get 5% off of the THIRD unit you buy! Welcome to the hoarders club.

    Those 7219 modules are cheap and much fun to master. We used those with 8x8 LED matrixes a while back. You might find some useful info at http://forums.parallax.com/discussion/152692/multiple-8x8-led-matrix-control-with-max7219
  • Jeff HaasJeff Haas Posts: 421
    I've done a couple of projects with those 8x8 modules. They're fun but kind of a pain in the neck. Two reasons - 1. The clone MAX 7219 chips don't all fall within spec and act weird (search for fake MAX 7219, there is a bunch of info out there). 2. I discovered that some of the pre-assembled boards had cleverly omitted the electrolytic cap! So the shipper saved a few cents, and the boards worked, but there were all these odd errors...

    Eventually I noticed the empty space under the LED matrix, and added the caps, and performance improved...but I still got weird drop-outs here and there, once I had chained a few modules together. One or two would work fine, more than that...maybe, maybe not. Of all the stuff I've ordered, those little matrix boards have been the most annoying.

    I hope this 7-segment display will be a bit better. I only ordered one for now. With just one clone MAX 7219 chip it should be OK.
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