In radio engineering and telecommunications, standing wave ratio (SWR) is a measure of impedance matching of loads to the characteristic impedance of a transmission line or waveguide. Impedance mismatches result in standing waves along the transmission line, and SWR is defined as the ratio of the partial standing wave‘s amplitude at an antinode (maximum) to the amplitude at a node(minimum) along the line.

The SWR is usually thought of in terms of the maximum and minimum AC voltages along the transmission line, thus called the voltage standing wave ratio or VSWR (sometimes pronounced “vizwar”). For example, the VSWR value 1.2:1 means that an AC voltage, due to standing waves along the transmission line, will have a peak value 1.2 times that of the minimum AC voltage along that line, if the line is at least one half wavelength long. The SWR can be also defined as the ratio of the maximum amplitude to minimum amplitude of the transmission line’s currents, electric field strength, or the magnetic field strength. Neglecting transmission line loss, these ratios are identical.

The power standing wave ratio (PSWR) is defined as the square of the VSWR, however, this deprecated terminology has no physical relation to actual powers involved in transmission.

SWR is usually measured using a dedicated instrument called an SWR meter. Since SWR is a measure of the load impedance relative to the characteristic impedance of the transmission line in use (which together determine the reflection coefficient as described below), a given SWR meter can interpret the impedance it sees in terms of SWR only if it has been designed for that particular characteristic impedance. In practice most transmission lines used in these applications are coaxial cables with an impedance of either 50 or 75 ohms, so most SWR meters correspond to one of these.

Checking the SWR is a standard procedure in a radio station. Although the same information could be obtained by measuring the load’s impedance with an impedance analyzer (or “impedance bridge”), the SWR meter is simpler and more robust for this purpose. By measuring the magnitude of the impedance mismatch at the transmitter output it reveals problems due to either the antenna or the transmission line.

https://en.wikipedia.org/wiki/Standing_wave_ratio

https://www.jaredwolff.com/finding-the-best-tvoc-sensor-ccs811-vs-bme680-vs-sgp30/

# Install required packages
sudo apt update
sudo apt install -y python3-pip libffi-dev

# Install Docker Compose from pip (using Python3)
# This might take a while
sudo pip3 install docker-compose

Source: Docker and Docker Compose on Raspberry Pi OS | With Blue Ink

Software Serial Buffer Expansion

The change for software serial ports require a simple modification of the file:

<base Arduino folder>\hardware\arduino\avr\libraries\SoftwareSerial\SoftwareSerial.h

Change:

__#define _SS_MAX_RX_BUFF 64 // RX buffer size

To:

__#define _SS_MAX_RX_BUFF 256 // RX buffer size

Hardware Serial Buffer Expansion

The change for hardware serial ports require a simple modification of the file:

<base Arduino folder>\hardware\arduino\avr\cores\arduino\HardwareSerial.h

Change:

__#define SERIAL_TX_BUFFER_SIZE 64
__#define SERIAL_RX_BUFFER_SIZE 64

To:

__#define SERIAL_TX_BUFFER_SIZE 256
__#define SERIAL_RX_BUFFER_SIZE 256

Btw, you can copy the SoftwareSerial.cpp and h files from the Arduino directory in to your project directory and then include it with “(quotation marks) instead of the < (pointy brackets). If you do this, make sure to also change the #include <SoftwareSerial.h> in your copy of SoftwareSerial.cpp to “SoftwareSerial.h”.
~you use <pointy brackets> to include files from arduino libraries and
“quotes” to include from project directory.

Source: Internet of Home Things » Expanding Arduino Serial Port Buffer Size

Serial.write() just sends raw bytes of data.

Serial.print() converts and displays data in human readable forms (ASCII).

Source: Why Serial.write() instead of Serial.print()

Source: How to determine the capacity of the JsonDocument? | ArduinoJson 6

https://create.arduino.cc/projecthub/rafitc/what-is-watchdog-timer-fffe20

The architecture of this number format is the following:

S: sign
E: exponent
F: faction (also referred to as the mantissa or significand)

calculation would be = (-1)^S * 2^(E [dec format]-127) * (1.F)[Base 10]

Source: How are floating point values converted in Schneider Electric energy meters?

https://www.modbustools.com/download.html

https://www.modbusdriver.com/diagslave.html