Memo: Digital PID controller

Digital controllers are more expensive to build in simple applications than analog counterparts but they are universally easier to implement at all scales. Digital controllers are limited by their sampling rates while they are capable of reaching steady state in a finite time and have much greater noise tolerance. Continuing from the last memo concerning analog PID,… Continue reading Memo: Digital PID controller


DIY Memo: Cross-compile ARM on Windows

Just a quick memo for setting up the toolchains for building ARM firmware on Windows platform. Software recommendations First, download and install the following software: A source code editor that supports debugging (Atom, Visual Studio Code, Eclipse, etc.) MinGW - GNU ARM Toolchain - J-Link Software and Documentation Pack (can be skipped, see below)… Continue reading DIY Memo: Cross-compile ARM on Windows

Memo: Design an analog PID controller

A controller transforms a plant (uncontrolled process) into a controlled system. A controller alters the input signal of the plant in order to correct the output error, which is the difference between the momentary output of the entire system and a reference value. The most popular controller in education and industry is the Proportional-Integral-Derivative controller (PID… Continue reading Memo: Design an analog PID controller

Memo: Thermodynamic processes

When investigating thermodynamic systems, especially gaseous systems, scientists often keep one of the three variables (pressure, volume, temperature) at constant and vary the remaining two. The act of fixating one variable and changing the others gives rise to thermodynamic, conjugate variable processes: Isobaric: constant pressure. Isothermal: constant temperature. Isometric / Isochoric / Isovolumetric: constant volume.… Continue reading Memo: Thermodynamic processes

Memo: Chemical bonding models

Beyond the level of individual atoms, atomic theory also concerns itself with the mechanism of molecular bonding and the geometry of molecules. There are three relevant chemical bonding models nowadays: Valence shell electron pair repulsion theory (VSEPR): the simplest, most primitive model based on electron field repulsions and Lewis structure. Valence bond theory (VB): a modern… Continue reading Memo: Chemical bonding models

Memo: Atomic models

Atoms are composed of subatomic particles whose quantity and arrangement affect their properties. The scientific theory correlating subatomic particles' quantity, their arrangement in an atom, and the atom's properties is called "atomic theory". Atomic theory attempts to explain how certain electron configurations affect the reactivity of elements, how certain elements are polarized while others aren't,… Continue reading Memo: Atomic models

Memo: Thermodynamics in Chemistry

All energy transferences are done in two ways: by heat or by work. In any given system and any given process, the total energy transferred is the sum of the heat transferred and the amount of work transferred. This says nothing about the ratio of work and heat in the total energy, or why energy can only… Continue reading Memo: Thermodynamics in Chemistry

Memo: Gas laws

Historically, the proportionalities of temperature, volume, and pressure of an ideal gas are described in pair empirically by Boyle's law (pressure-volume), Charles' law (temperature-volume), and Gay-Lussac's law (pressure-temperature). These early gas laws; along with Avogadro's law, which links the study of gas in Physics to the number of molecules in Chemistry; are combined to form the modern ideal… Continue reading Memo: Gas laws

Memo: Chemical equilibrium

Some chemical reactions are reversible. The ingredients, or reactants, interact to create products in the forward reaction while the products (ions, chemical compounds, and thermal difference) interact with one another to recreate the reactants in the backward reaction. These reactions are technically neverending although, in practice, the chemical reaction is considered completed when these two opposite processes… Continue reading Memo: Chemical equilibrium

DIY Memo: ESP8266 v12 analog I/O

This is an amendment to the previous ESP8266v7 memo. More specifically, the I/O pins don't behave exactly as described by internet sources. A little bit of background: I was presented with a challenge to read from an analog sensor and send the reading through wifi network to the cloud. This can be accomplished easily using… Continue reading DIY Memo: ESP8266 v12 analog I/O