Tag Archives: monitor

PaPiRus Netapp – Monitor your network with Raspberry Pi

Use PiSupply’s PaPiRus ePaper display to monitor your network with a Raspberry Pi.

Over the past few days I have been converting my “Speedtest-cron” code to work on the PaPiRus from PiSupply. Whilst going over the code, I decided to start a new Git Repository and rename this version to “PaPiRus Netapp”.

PaPiRus Netapp – Monitor your network with Raspberry Pi – [Link]

DIY Home Energy Meter

A new tutorial by The DIY Life is for building a home energy meter that provides information about power consumption and cost estimates for the month.

Using Arduino and some other components you can build your own energy meter that measure the supply current to your home through a CT (current transformer), current, power, maximum power and kilowatt hours consumed. The cost of electricity used to date can be added and displayed easily.


Electronics you need to build this project:

  • Arduino Uno
  • LCD Shield / LCD Screen
  • CT – Talema AC1030
  • 56Ω Burden Resistor
  • 10µF Capacitor
  • 2 x 100K Divider Resistors

If you are not familiar with Arduino or LCDs you can check these articles by The DIY Life to learn more: getting started with Arduino, connect an LCD screen

First you have to build the current sensor by connecting the CT to the Arduino and setting a right voltage reference due to the Arduino 0-5V input range. As shown below, this is the way you should connect the CT to the Arduino.


This code should be uploaded to your Arduino to run the project. It already has a scaling factor that can be adjusted due to the components you choose in your circuit.If you don’t want to use or don’t have an LCD screen, you can also modify the sketch to output to the Arduino IDE’s serial window as described in this code.

For more information on how to choose different components, how to calibrate them, and to learn more details about wiring and coding, you should check this tutorial out.

The first number displayed is the instantaneous current followed by the instantaneous power. On the bottom line, the kilowatt hours used since reset and then the maximum recorded power since reset. Check the meter in action:

Tiny OLED PC Performance Monitor


Rupert Hirst build a tiny OLED PC performance monitor based on Psyrax’s serial monitor. The display monitors CPU and GPU temperature and activity etc. He writes:

After a recent purchase of a Nvidia GTX1080 graphics card, 4k monitor plus Doom(2016), I thought it would be great to see some external telemetry… from my exorbitant purchase.
Then, I Stumbled upon on Psyrax’s “Serialmonitor” GitHub repository! Armed with an Arduino ProMicro plus a 128×64 pixel OLED display, I compiled the source code. After compiling Psyrax’s windows application in Visual Studio, I got to work.

Tiny OLED PC Performance Monitor – [Link]

CO2, temperature and humidity monitor


An open source CO2 monitoring project from Roving Dynamics:

The project described below uses a MH-Z16 or MH-Z19 CO2 sensor and a DHT-22 (or DHT-11 if less accuracy is required) to measure the Temperature and Humidity. It has a 4 line by 20 character LCD Display to show the current readings and status, a warning alarm and two relays which can be triggered on a low CO2 (Generally above 1000 ppm) normally to switch on an extractor fan and a high level (4000 ppm) which will trigger a warning device such as an external alarm. There are two models I used the 0 to 5000 ppm device here but the code will be the same for the 0 to 10000 ppm model

CO2, temperature and humidity monitor – [Link]

30A, PCB-level supply monitor has integrated 300 µΩ sense resistor

>Designed to simplify board-level energy measurements, the LTC2947 power and energy monitor for 0V to 15V DC supply rails eliminates the need for an external sense resistor to measure current. by Graham Prophet @ edn-europe.com

Choosing a sense resistor, Linear says, is not an easy task, especially when dealing with high currents, where available sense resistors can dissipate too much power, occupy a lot of board space or have a large impact on measurement accuracy. The LTC2947 integrates a 300 µΩ temperature-compensated sense resistor to alleviate these concerns, providing users with a simple 24 mm² solution that provides up to 1.2% accurate energy readings at up to ±30A.

30A, PCB-level supply monitor has integrated 300 µΩ sense resistor – [Link]

Sunburn Monitor – A UV monitor

Sunburn Monitor is a UV monitor with sound-based indication. It calculates the max sun exposure before sunburn based on your skin type.

The project was published over hackaday.io by [Quarterturn].


It’s based around SI1132 light sensor from Silicon Labs. SI1132 is a UV index and ambient light sensor with I2C interface and it’s available in 10-lead 2×2 mm QFN package. Sunburn Monitor uses ATMEGA168 MCU where the firmware was developed using Arduino environment.

The design has a protection transistor Q1 (DMP2035U-7) in the input, we covered in a past blog how to protect you circuit from reverse voltage, and Q2 is used to enable/disable the supply voltage of the sensor.

Sunburn Monitor powered by a 3v CR2032 battery with power management relies primarily on either deep sleep via hardware interrupt or watchdog timer interrupt for sleep-wake-sleep monitoring cycles, according to [Quarterturn].



The source code and the design files, using Eagle CAD, (SCH & BRD) can be found here.
[Project page over hackaday.io]

Low-side I/V sensing IC, with internal power calculation


Maxim Integrated has posted details of the MAX44299, a low-side current, voltage, and power monitoring circuit that provides an analogue output current proportional to the measured current, voltage, and the internally calculated instantaneous power. The power monitor offers high precision and integration in tiny size.

Instantaneous power is calculated internally by multiplying the load current and a fraction of the load voltage set by an external resistive divider. All three outputs are scaled to a full-scale current of 100 µA. An additional output current of 100 µA is available at the reference (REF) output; this current can be used to create a reference voltage for the ADC that is being used to measure the power, voltage, and current signals.

Low-side I/V sensing IC, with internal power calculation – [Link]

Automatic monitor brightness controller


Dilshan Jayakody build a auto monitor brightness controller that adjusts your monitor brightness according to lighting conditions. He writes:

The sensor unit of this system is build around PIC18F2550 8-bit microcontroller. To measure the light level we use LDR with MCU’s inbuilt ADC. The control software of this unit is design to work with Microsoft Windows operating systems and it use Windows API’s DDC/CI related functions to control the monitors/display devices.

Automatic monitor brightness controller – [Link]

Hacking a Blood Pressure Monitor


by Eduardo @ edusteinhorst.com:

I’ve been meaning to hack my blood pressure monitor for a while, and I finally got around to doing it! So, the idea is to mod a regular electronic blood pressure monitor to make it wireless and connected to the Internet, much like iHealth BP5 or Withings’. That makes detecting trends in your blood pressure much easier, since you can chart the data and even correlate it with other health data, such as how much sleep you’ve been getting, your weight or your level of activity. The model I have is the EW3106 from Panasonic. It’s quite old but from what I’ve seen the design hasn’t changed much throughout the years.

Hacking a Blood Pressure Monitor – [Link]

LTC4282 – High Current Hot Swap Controller with I2C Compatible Monitoring



The LTC4282 is an energy monitoring Hot Swap controller with dual MOSFET drive to enable 100A and higher current board designs. The LTC4282 ensures safe board insertion and removal from live 2.9V to 33V backplanes by controlling external N­channel MOSFETs to gently power up capacitors, avoiding sparks, connector damage and system glitches. High current hot-pluggable boards utilize parallel MOSFETs to reduce voltage drop, but all of these MOSFETs require large safe operating area (SOA) to ride through overcurrent faults. By controlling two matching current limited paths, the LTC4282 halves each path’s SOA requirements, reducing MOSFET costs in high current applications (>50A). The LTC4282 provides a rugged, compact solution for hot plugging and monitoring, especially in high power circuit boards in servers, network routers and switches, and enterprise data storage systems.

LTC4282 – High Current Hot Swap Controller with I2C Compatible Monitoring – [Link]