Bluetooth Low Energy IOT

  If you are unsure about your car battery and charger capacity, you can use this diy battery logger in 12V plugin connector to measure it. For this logger I used STM8S103 module and HM-10 Bluetooth Low Energy module and Android Smartphone as displaying device. STM8S103 bluepill module: HM-10 BLE module Android application screenshot: Hardware schematic diagram drawn with KiCad: STM8S103 Firmware was developed with ST Visual Studio with COSMIC C compiler in Windows PC.  ST Link V2 as programming /debugging interface. Kicad 3D images of project hardware: And actual prototype images: Android application screenshots of battery voltage logging: Project files  for KiCad , ST Visual Studio and Android apk to download: https://github.com/joukohak/batlog

Cheap and simple DIY bluetooth low energy digital oscilloscope made with JDY-08 BLE module and STM8S103 module and Li ION battery. Android application is developed to display oscilloscope data.  STM8S103 is 8-bit microcontroller with 1024 bytes RAM and 8 kbytes Flash memory. It stores 300 samples of 10 bit ADC data to RAM memory. Minimum sampling period is 5 us (200 kSamples/s).  ADC data is sent trough BLE lin k to Android smartphone application.  Circuit diagram

 Low Energy Solar Fridge controller DIY My target was to make very cheap and  very low energy  refridgerator controller to 12V solar system. Low energy fridge can be implemented with container type freezer with AC power and inverter (1000W) to be controlled by designed controller. Schematic diagram and PCB  Circuit diagram and printed circuit board was made with KiCad developement tool. Main components of the controller are STM8S103 (module or IC), BLE module JDY-08 and LCD display 16x2 lines. Printed circuit board as KiCad 3D: STM8S103  program was developed with ST Visual Studio Developer and COSMIC STM8 C-compiler. 3D printed case 3D printed cover using PLA filament: Android application Android application developed with Android Studio. Android phone can be used to adjust temperature setting, control inverter and display temperature / battery voltage information. Link to de...

Bluetooth Low Energy module JDY-08 used in Low Energy Solar Fridge controller Bluetooth Low Energy module used in STM8S103 8-bit microcontroller based controller to use as Ultra Low Energy 12V Solar  Fridge from AC Freezer.    Modified sine wave inverter 1000W  including remote control interface modular RJ-11 connector.     Energy consumption has been with 60 l  Midea  freezer on 12 V  solar system about 8 Ah/ 24h. Printed Circuit Board is designed with KiCad tool and STM Visual Studio IDE used to STM8S103 firmware developement. BLE module used as wireless link to Android application developed on Android Studio. Graphic User Interface in Android application allows temperature setting, inverter control ,battery voltage show, fridge temperature show and voltage/temperature log graph show. Link to design files:  https://github.com/joukohak/solarfreezer