HT1621B Display controller Breakout Board

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As a part of my work, I needed to drive an LCD segment display. Now, these displays are somewhat of a mixed breed between LCDs and 7 segment displays. They look sleek like LCDs, and are structured like 7 segment displays. However, they cannot be controlled just by toggling the segment pin of a particular segment high. They actually expect something of an “AC” signal to keep them on.

There are Arduino libraries that allow you to do this : You can find it here http://playground.arduino.cc/Main/SevenSegmentLibrary . However, if you are going to need 8-9 pins to control one character, you’ll find you will quickly run out of pins. Thankfully, these segments are very common, and so of course, there are controller ICs that will drive these displays, and let you offload the cumbersome task of generating the AC signals to drive those LCDs. The HT1621B is the perfect LCD segment controller IC for this job.

You just have to send messages serially to the HT1621B (in the right format of course), specify the necessary parameters, and the controller will take care of the rest. You can use the Arduino library for the HT1621B here.

HT1621B Breakout board

While working on this, I found it rather difficult to find an existing breakout board for the HT1621B, which is in the SOP48 package. I designed a board for it so that I could test it out. You can order the board with HT1621B controller ( if you are in India ) at the Amazon link here : http://amzn.to/2bRSKVb .

If you want to get just the SOP48 breakout board, you can head over to OSHPark (link below).

Order from OSH Park

I hope this is useful !

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Physical Integrity

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Software can be tested. Test cases can be supplied, performance can be measusred and the output verified. In open-source software, the code can also be read and one can understand the thought and techniques and other intricacies and decisions that went behind making that piece of software. In other words, the entire body and soul of the product is out there in front of you.

All about coffeeThe same can be known about coffee, if you put in the effort. I recently came across an image that expresses exactly that. You can know where the coffee originated, the processes it went through, the people involved and other details. The complete life of the product (though to many people coffee is more than just a product, more like a piece of art) can be put in front of you, the user, the consumer, anyone who deigns to ask.

Why not with hardware ? And when I say hardware, I don’t mean electronics. Sure, hardware, electronic or otherwise can be “tested” for particular things. Stresses, strains, temperature responses, resistances, brittleness, opacity and a ton of other things can be “tested”. Electronic goods which are assembled have QR codes on every major component in them, but they don’t tell you where they were made, what processes went into making it and the like.

I can understand that there is the “too much information” argument, and about the usefulness of it. But I liken this idea to that of a “physical MD5 checksum”. There is an “MD5” checksum to check the integrity of code, to see if the product as it was packaged and supposed to be. Having a physical MD5 checksum, could open up quite a few possibilities.

– You could actually be able to check if things actually are what they claim to be. With the advent of 3D printing, this should be a pretty useful testing probe.

– You could distinguish your “Made in Taiwan” from “Made in Korea”. Win for activism and awareness, not such a pleasant thought for corporates and governments.

– You could know how your product is made, where it is made, if the product you got is the one you paid for or one with a “cheaper / less reliable / more hazardous” component

– You could actually know if and how your Apple product is worth the “premium” that you pay for it over other alternatives, without having to rely on marketing content manufactured for you by any company

There is quite an obvious con too. Manufacturing secrets and processes could be revealed, which in most cases are patented trade secrets and often minor things are differentiators between products, and wouldn’t do well to be revealed. But then, this entire idea is about accountability and openness, so I guess there are decisions and trade-offs that would need to be made.

One more disadvantage would arise from having too much information. Knowing too much and having too many things to choose from, can paralyze you. Nevertheless, choices can be broken down, information can be prioritized, and made manageable. There are complete industries and professions that do that. After all, where would we have been if we had not accepted use of fire because it could burn if improperly used ?

P.S. I hereby certify that this entire thought was not influenced by any sci-fi movies, but by the simple question I had when I was in a supposedly career-deciding examination – What if my food or drink which was instructed to be left unprotected in a common waiting area was tampered with ? There should be a checksum for that.

P.P.S. Feel free to start a discussion with me by dropping me an email 😉

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