Aug. 27, 2018

I were hooked with silicon and eposy

August 27, 2018: I exported some content from, this post was in different title "One of very boring titles", but I changed this to silicon and epoxy at a funny way to look at micro controller and embedded system. The original content is below.

So let cut to the chase. I am starting a personal blog of various topics from technical to rambunctious thoughts of daily life. The technical stuff will be on electronics with Internet of Things (IoTs) for home applicants and basic setups of weather station. You can start look at other pages now :)

Another blog about IoTs!!! It sounds like a hit word, a buzzer word, a word for attraction, nothing else, and I agree. But in that IOT-mini ocean of information, I found helpful nuggets I played with. I thought some stuff will be a part of our ‘remote control’ for coming time.

The less technical will be non-topical. You are going to disappointed, but this one of my approach, let the expectation low, so the life is easier, and I’m will be happier, for a moment. Punch intended.

In coming days, I will put together some of my works with ESP8266, a low cost micro controller with internet connectivity. I have played with this board for almost a year now, and so far I burned 3–4 boards. This is one of metrics I used to rate my not-happy accidents when playing with electronics. Just like burn rate of startup! For me it is a burnt-and-smelly room!

I hope some will ask why electronics and ESP8266. Good question, well, an appropriate question, actually! I were trained in environmental engineeringat Hanoi University of Technology. The school’s name was added with “Science and” a few years ago, making the abbreviation from HUT to HUST. Sometimes, I proudly responded to some one asking what was my major, and I said double Es! with the implication to “Electrical Engineering”, but not wrong if one pressed for “Environmental Engineering”. So, of course, I were an electronic fanboy.

So where was I? I was working with pH-control system for a microalgae cultivating vessel in 2013 in the States. At that point, I would love something that have a knob to turn like a radio button, then something else that can closes the gas line for me, which later I googled it as “solenoid valve”. Those are examples of my know-hows by then. In 2014–2015, I found a system used in aquarium to control pH, salt, oxidation state, oxygen, and some others. To be accurate, my friend named L.S. showed me a photo that someone in Poly Campus used. So, here is the first important point, knowing that the people in Poly Campus is better with commercial systems, I trusted them should use good systems, and quickly learned the specifications. And with the cost about $500, I knew that I can convince my advisor to sponsor me.

Well, many details to fill in here. But my advisor was my boss as well. Any purchase or order needed to have his consent or at least no objection. The absence of objection is a new level that I learned later in 2016. That is another eureka moment working with my advisor to learn that there is new level of trust or a let-shoot-myself-in-the-foot-if-something-bad-happens decision. So many hyphens but much less compared to when I did not not get a clear ‘go’ from my boss and decided myself that I was going to jump into the water. Was any water there, what was I thinking?

So where was I, again? Long story shorts, I learned about Arduino, a friendly-entry board, for non electrical engineers that subsequently I built a pH-DO-temperature monitoring unit, a light control using high-power LEDs and pre-defined solar pattern with a real-time clock unit. It was lot of sweats, and funs (after lots of sweating ). (Don’t let a cute or successful video fools you). When I had one unit, it was great because you did not need to communicate with other units. Since I had three modules working with a 2.5L reactor, the communication between unit became a pressing issue. I were beaten up trying to get serial communication between Arduinos. Anyway, being able to write the data into SD card, or connect them via ethernet cable to download file were more than good-enough. The marriage of C-based MCU like Arduino and Linux-based MCU like Yun Shield (I used Dragino’s btw) was another topic, but that is how I managed to build a turbidostat to measure and control biomass of microalgae through an infrared sensor used in washing machines.

So what up with my story? Here is why ESP8266 came in to picture of my life. I like internet, I like connection, I like electronic, I like low cost, I like easy-learning curve, and these led me to ESP8266. I have a bigger sister of ESP8266 called ESP32. ESP32 is dual-core (fancy) low energy bluetooth, a lot more Analog-to-Digital converters, but the board is still challenging to develop by people like me. So I’m happy with ESP8266 with only ADC converter, single-core MCU that costs about $2-3 on Aliexpress.

So yes, that is how a boring title ends!

Orignal content was posted on Medium on April 4, 2018
* * *