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Do your test stations still communicate with smoke signals?
In the olden days, many would wait until a piece of equipment began to smoke before paying attention to it. Imagine you have a test station that tests many individual units for a long period of time. Most months, nothing notable happens. Every once in a while, a test unit will fail. If you only check on these devices once a month, it could be almost 4 weeks before you knew there was a problem.

Perhaps your test station may be smart enough to cut power off before actual smoke is released. It might even turn on a helpful light on the front panel, but that still means an operator must walk over to the test rack and see if something is wrong.

What if a device has been drawing 2500mA for that last 6 month and then begins to draw 2750mA? If it is still within spec, most test stations will not tell you something has changed, unless an operator walks up and checks on things. It doesn’t have to be that way.

Welcome to the age of IoT
For those of you who came to the Open House a few weeks ago, the picture in figure 1 will be familiar. You probably connected your cell phone to our IoT WiFi router, Ireland (did you think I would name it anything else?) and then went to the live WEB page for the ESP8266 board.

In case you didn’t make it, I will tell you what you would have seen. There is a welcome at the top of the page and a few buttons; one said ON the other said OFF. When you pushed the button on your cell phone the little board sitting on the desk turned on/off the Yellow LED and then updated the page with the current status of the LED.

Depending on your personality, you might think that was not very impressive or The Most Awesome Thing Every! We know who watches The Big Bang Theory don’t we. So, what’s the big deal about turning on a little LED? Well, not much. But having an interactive web page generated by a stand-alone device is a big deal. Not only can you get real time updates, but you can make changes to the test station from your mobile device.

For security reasons, we limit these interactions to devices connected to the same network, but theoretically you could control and get updates from anywhere in the world.

IoT presentation with electronic module on paper.

Figure 1 IoT interactive display at the Open House

Owl Post
Suppose you wanted to get an email from your test equipment when a parameter changed by 10% or if a DUT (Device Under Test) failed and the test station automatically removed it from power. How would you go about doing that? The device we used is a WiFi module available on the “Inter-webs” for under $10. You could talk to it using AT commands from another MCU that runs your test station. You give your system a WiFi name and login password and it will connect to your WiFi. If you just want an interactive web page while within the company WiFi you are almost there. You will have to write HTML code from an 8-Bit MCU, but you’ve got that right?

If on the other hand you want to get an email from your test station while you are at a conference 3000 miles away, or at 2 a.m. because it’s just that important you will need to set up an email account and have the device log into the account and send an email. This is different from the IFTTT emails (if this than that) that send off a predefined email that is just waiting for a trigger. Those are static emails and don’t contain any live data. They can be very useful, but that usefulness is limited.

The kind of email I am suggesting has real data in it. It is like getting an email from a live person, depending on the person it might be very lifelike. You could send information like “Device 63 just exceeded 3A and was removed from service,” or a status update, “Currently there are 250 units operating within design, 12 are consuming 10% more current than 1 week ago.”

Because you are in control of the message and you have a microcontroller attached to the test station, you can collect data and transmit it at any time. The data you transmit is limited only by the hardware you design.

Who’s on first?
Maybe you don’t run life tests, but you run batch tests and the burning question is will we have enough units to ship today. Your webpage can be very elaborate and can be updated regularly during the test. Depending on the MCU you use, you might even display a graph. Everyone in the company, with a need to know, could look at the page and see the progress of the test. When the test is complete, it will display the final test results.

The world is changing, are you?
On the small webpage I made up for the demo, I posed the question, “How will you use this technology?” Technology is changing rapidly. In order to maintain your competitive edge in the marketplace, you must change as well. Make use of the new tools and ideas that are available. Be creative. Who knows, you might even have some fun.

Final thoughts
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