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Welcome to my new Weather Widget Project. Earlier I have posted an article on the weather widget, that uses a 0.96" OLED display to display the weather parameters. The main problem in the earlier version is that the display is very small in size, so you have to come very close to it for reading the parameters. That's why it was always in my mind to upgrade it to a larger color display with a nice 3D printed enclosure.In this post, I will show you how to make a Weather Widget by using ESP8266 and a 2.8" touch screen display. The device retrieves localized weather information from https://openweathermap.org/ by WLAN and displays it on the Display module.Visit my website for more interesting projects: https://www.opengreenenergy.com/The Widget displays the following things:1. Current Time with Date2. Current Day Weather Information like Temperature, Pressure, Humidity, and Rainfall.3. Future forecasting for 7 daysCredit :I would like to give credit to my friend Dani Eichhorn who did all of the programming parts. He is updating the software on his Github page regularly with new features. You can visit SquixTechBlog to see more projects on ESP8266.Prepare the Wires:My plan is to place the weather display circuit inside a 3D-printed enclosure. But the enclosure that I am going to use is very compact, and there is little room to keep the Wemos board along with the connecting wires inside the housing.So, we have to select thin wires to make the connection between the display unit and Wemos Board. Here, I have selected 30 AWG single-stranded wires.Cut 14 numbers of wires with equal length by using a Nipper.Then strip out the insulation from the wires by using a Wire Stripper.Solder Wires to the Display Unit:The TFT display has pre-soldered straight header pins to mount it to the breadboard or any other shield. You have two options1. Desolder the header pins from the PCB and then solder the wires to the soldering pads2. Directly solder to the header pinsI prefer the second one, it is much easier and requires less effort and skill.Before soldering apply a small amount of soldering flux to all the header pins. Then tin the header pins by using a small amount of solder on the soldering iron tip. Tinning is required as it makes the soldering process easier and strong bonding between the wire and header pins.Finally, solder the wires to all the header pins as shown in the above picture.3D Printed Enclosure:I have modified the enclosure in Autodesk Fusion 360 by taking reference from a nice model available in Thingiverse and designed by smily77. The dimensions of all the components are measured by a vernier caliper then the same were considered during the design.The enclosure has 3 parts:1. Housing Body2. Back Cover3. Base CoverDownload the STL files from ThingiverseI have used my Creality CR-10 Mini 3D printer and 1.75 mm white PLA filament to print the parts.My settings are:Print Speed: 60 mm/sLayer height: 0.2mmFill Density: 20%Extruder Temperature: 210 deg CBed Temp: 60 deg CInstall the Display:In this step, you have two options1. First Install the Display into the enclosure then solder the wires to the Wemos Board2. Make the wiring between display and Wemos board first, then install them into the enclosure later.I have shown both ways in the above pictures. The pictures themselves are self-explanatory.My personal preference is the second option.Wiring Diagram:The wiring diagram is very straightforward. You have to connect the TFT display module ( ILI9341 ) pins with Wemos pins as per the schematic diagram. The schematic diagram is shown above. You may also follow the following pin mappingTFT Display->Wemos ( ESP8266 )VIN -> 3.3VGND -> GNDCS -> D1RESET -> RSTDC -> D2SDI -> D7SCK - D5LED -> D8SDO -> D6T_CLK -> D5T_CS -> D3T_DIN -> D7T_DO -> D6T_IRQ -> D4Make the Circuit:First, download the schematic diagram, then take a printout. It Is really handy during the soldering and you will save a lot of time also. The most important thing is any mistakes in the connection may damage the display module or Wemos board. During the making of this project,I have fried my display unit touch screen IC due to some mistake in connection.Prepare the Arduino IDE for ESP8266 Board:The ESP8266 module isn't part of the Arduino-IDE, so we have to install it first. You can easily install it by going through the following steps:1. Start Arduino IDE and open the Preferences window.2. Enter https://arduino.esp8266.com/stable/package_esp8266com_index.json into the File>Preferences>Additional Boards Manager URLs field of the Arduino IDE. You can add multiple URLs, separating them with commas.3.Close this window with the OK Button. Open Boards Manager from Tools > Board menu and select the correct ESP8266 board.4. Now you can choose LOLIN(WEMOS) D1 R2 & mini. Set the CPU frequency to 80MHz, Flash Size to "4MB (FS:3MB OTA:~512KB)", and the COM port.Download the Code and Libraries:You can download the Arduino code and supporting libraries from the following links.Arduino Code:https://github.com/ThingPulse/esp8266-weather-station-colorLibraries:1. Mini Grafx by Daniel Eichhorn2. ESP8266 WeatherStation by Daniel Eichhorn3. Json Streaming Parser by Daniel Eichhorn4. ThingPulse XPT2046 Touch by ThingPulse (forked from Paul Stoffregen), if you had previously installed the original XPT2046_Touchscreen then you need to uninstall that one!After downloading the library unzip it and installed it with your Arduino Library Manager inSketch > Include Library > Manage Libraries...Get OpenWeatherMap API Key:The Weather Station real-time data is obtained from the OpenWeatherMap website. So you have to get the OpenWeatherMap API Key.Now you can choose the free plan in the first column. There is no cost to apply for a free plan, which is more than sufficient for our requirements. Only the limitation of using the free plan is that you are limited to 60 calls per minute.Now click on Get " API Key " then create a new account by filling up your credentials.Note down the API key which will be required in our code in the next step.Upload the Software:After setting up Arduino IDE and installing all the libraries we can move to upload the code into the ESP8266 board ( Wemos D1 Mini Pro or any other board )First, you have to unzip the code downloaded in the earlier step and then save it somewhere on your PC or Laptop. Remove the word master from the folder name, the final name shall be " esp8266-weather-station-color "Now open the folder and click on "esp8266-weather-station-color.ino "In one of the tabs, the IDE opened settings.h. Go through the file and adjust the two handfuls of configuration parameters. They are all documented inside the file directly. Everything should be self-explanatory. Most importantly you will need to set the OpenWeatherMap API key you obtained in a previous step.Now you are ready to upload the code, just hit the upload arrow button.Install the CoversAfter mounting the display unit and circuit board, we can move to box up the housing by using the two covers. The enclosure is designed with very tight clearance, so you don't need any glue or screw to hold the covers.Align the cover with the slot in the enclosure and press it all around, you are done. The smaller cover is for the base part and the larger one is for the backside of the display part.TestingIf you are successfully uploaded the code into the ESP8266, you will immediately notice the display on the front page by searching the WiFi Network for connection. After connecting the device to your WiFi router, it will update the time and weather data from the web.Now you will be able to see all the weather information along with all other parameters on the TFT display. You can swap between the different pages by using the stylus or touching with your finger.Note: In the beginning, you will be asked to touch the screen for calibrating the touch screen display.I am super happy with the final outcome of this little gadget. You may gift this little gadget to someone on any occasion.

Hi! :)I am an Electrical Engineering student from Croatia and I built this device as a part of one course at University last semester. It is a fidget spinner which uses Persistence of Vision effect which is an optical illusion whereby multiple discrete images blend into a single image in the human mind.The text or graphics can be changed via Bluetooth Low Energy link by using a PC application that I have programmed in LabVIEW or by using a freely available smartphone BLE app.One of the most important characteristics is that the displayed graphics doesn’t depend on rotation velocity thanks to its innovative solution for keeping the track of rotation angle. Meaning that the displayed graphic is perceived the same at both, higher and lower rotational speeds (for instance, when the fidget spinner is slowing down when held in the hand).This is also one of the main difference between various POV device on the market (POV clocks, etc.) which must have a constant rotational speed in order for the image to be displayed correctly.It is also worth noting that all the components are selected to have the lowest possible energy use in an effort to prolong the battery life Technical DescriptionIt uses enhanced Microchip PIC 16F1619 microcontroller as its core. The MCU has built-in Angular Timer peripheral which uses omnipolar Hall sensor DRV5033 and one magnet to keep the track of current rotational angle.The graphics is displayed using a total of 32 LEDs, 16 green and 16 red light emitting diodes (nominal current 2mA). The diodes are driven by two 16 channel constant current shift register drivers TLC59282 connected in daisy chain.In order to have a remote access to the device, there is a Bluetooth Low Energy module RN4871 which communicates to the microcontroller via UART interface. The device can be accessed from either a personal computer or a smartphone.The device is turned on by using a capacitive touch button which is embedded under the solder mask on the printed circuit board. The output from the capacitive IC PCF8883 is fed to the OR logic gate BU4S71G2. The other input to the OR gates is a signal from the MCU. The output from OR gates is connected to the Enable pin of a step-down converter TPS62745. By using this setup I am able to power on/off the device by using only one touch button.Capacitive button can also be used to change between different modes of operation or for instance to turn on the bluetooth radio only when needed in order to save energy.Step down converter TPS62745 converts 6V nominal from the batteries to a stable 3.3V. I have choose this converter because it has high efficiency with light loads, low quiescent current, operates with a tiny 4.7uH coil, it has integrated input voltage switch which I use to measure battery's capacity with minimal current consumption and the output voltage is user-selectable by four inputs rather than feedback resistors (reduces BOM). The device goes to sleep automatically after 5min of inactivity. The current consumption in sleep is less than 7uA.The batteries are located on the back: Keeping the track of rotational angleThe rotational angle is tracked "by hardware“ rather by software meaning that the CPU has a lot more time at its disposal to do other tasks. For that I have used Angular Timer peripheral which is built into the used microcontroller PIC 16F1619.Input to the Angular Timer is a signal from Hall sensor DRV5033. The Hall sensor will generate a pulse every time a magnet passes by it. The Hall sensor is located at the spinning part of the device while the magnet is located on a static part for which the user holds the device. Since I used only one magnet that means that the Hall sensor will produce a pulse that is repeating every 360°.At the same time Angular Timer will generate 180 pulses per revolution in which every pulse represents 2° of rotation. I choose 180 pulses, and not 360° for instance, because I found 2° to be the perfect distance between the two columns of a printed character.The Angular Timer handles all that calculation automatically and will adjust automatically if the time between the two sensor pulses changes due to the rotation velocity changing. The positon of the magnet and Hall sensor is shown in the picture below.Remote AccessI wanted a way to change the displaying text dynamically and not by just hard coding it into the code. I have choose BLE because it uses a very small amount of energy and the used chip RN4871 is only 9 x 11.5 mm in dimension.Via BT link I am able to change the displaying text and its color - red or green. I can also monitor battery level to know when it is time to replace the batteries.The device can be controlled via computer application programmed in LabVIEW graphics programming environment or by using a freely available smartphone BLE applications which has the ability to directly write to the selected BLE Characteristics of a connected device.For sending the information from a PC/smartphone to the device I used one Service with three Characteristics, each identified by a Handle. PC ApplicationIn the top-left corner we have controls for starting up the National Instruments BLE server application. That is a command line application from NI which creates a bridge between BLE module on a computer and LabVIEW. It uses HTTP protocol to communicate. The reason for using this application is that LabVIEW only has native support for Bluetooth Classic and not for BLE. Upon successful connecting, the MAC address of a connected device is displayed on the right and that part is not grayed out anymore. There we can set the moving graphics and its color or just send some pattern to turn the LEDs on or off when the device is not spinning, I have used that for testing purposes. FontI generated English alphabet font using a freely available software "The Dot Factory“ but I needed to make a few modification before uploading it to the microcontroller.The reason for that is PCB layout which is "not in order“, meaning the output 0 from LED driver is maybe not connected to the LED 0 on the PCB, OUT 1 is not connected to LED 1 but rather to LED15 for instance, and etc.. The other reason is the software only allowed to generate 2x8bit font but the device has 16 LED for each color so I needed a 16bit high font.So I needed to make a software that would shift a few bits to compensate for PCB layout and combine them to one 16bit value.Because of that I developed a separate application in LabVIEW that takes the font generated in "The Dot Factory“ as input and transforms it to suit the needs of this project. Since the red and green LED PCB layouts are different I needed to use two fonts. The output for the green font is shown in the picture below. Programming jigOn the picture you can see the programming jig I have used to programe the device.Since, after every programming, I need to pick up the device and spin it to see the changes I didn't want to use standard programming headers or just solder the programming wires. I used Pogo pins which have a small spring inside them so they fit very tightly to the vias on the PCB.By using this setup I am able to program the microcontroller very fast and don’t need to worry about programming wires or the left-over solder after desoldering those wires. ConclusionTo summarize, I would like to point out that by using Angul Timer peripheral I successfully achieved a POV device which doesn’t depend on rotational velocity, so the quality of displayed graphics is kept the same at both higher and lower speeds.By careful design I managed to implement a low energy solution which will prolong the batteries life.As for the cons of this project I would like to point out there is no way to charge the used batteries, so battery replacement every now and then is required. No-name batteries from the local store lasted about 1 months with every-day use. Uses:This device can be used in a various promotional purposes or as teaching aid in electrotechnics or physics classes for instance.It can also be used as a therapeutic aid to increase attention for those with Attention Deficit Hyperactivity Disorder (ADHD) or calm symptoms of anxiety. The schematics and BOM are attached. The Gerbers have three separate circular boards - the front board (which holds the magnet), back side board, and a small circular ring to encrease the contact surface with the 608 bearing in the middle of the device.Also, I would like to thanks Simon from PCBWay for sponsoring the first version of the PCB :)3D output from Altium DesignerBill of Materials (BOM) in PDF format is available here:https://files.fm/down.php?cf&i=m6dx2ks8&n=BOM+%283%29.xlsxBOM in Excel format is available through "BOM(Bill of materials)" button on the top right of this page.