Tech Diary

Xiaomi Miflora sensor allows monitoring of the surrounding environment of the plant. It can monitor temperature, soil moisture, conductivity (acidity of the soil), ambience light. There are 2 versions of the sensor, international and Chinese version. Realistically, I cannot see the difference between the 2 versions. The left-hand side is the Chinese version and the right is the international version. Other than the packaging, the main difference is the price of the sensor. The International version cost 2x more. In other forums, there are discussions that the Chinese version cannot connect to the MiHome App. I have set my MiHome app to connect to China server and it is able to register the sensor correctly. For my usage, I will be connecting to Openhab to monitor the plants andusing  Thomas Dietrich MiFlora mqtt daemon  as the bridge between Openhab and the sensor. The International version is detected as Flower care and the firmware version is 3.1.9 wh...

The project has reached an operational stage with the following milestones. The original posts can be found at Starting a smart home project Smart Home Design V1 The Smart Home is controlled by Openhab2 using a Raspberry PI. After some initial instability, the system finally is able to be functioned smoothly. The main control panel is Habpanel and a sample of the main dashboard is as shown. Habpanel is one of the official UI supported by Openhab. It comes with some pre-defined widgets such as buttons, frames etc. For the pictures above, some of the widgets are custom widgets created by third parties such as the column of sliding switches, presence detection panel and the fan control panel. User can easily extend habpanel widgets because the widgets are written in AngularJS. There are 5 main types of communications protocols: 1. WIFI This is the main backbone used by all the devices. 2. Zigbee This is mainly used by Xiaomi sensors. 3. RF 433 MHz This is used by...

This post describes the control panel developed with a few open source software and libraries. The main purpose is to have a proof of concept that the various components can be put together to become a useful product. I have built a smart home system controlled using Openhab and the hardware switches are primarily using Sonoff switches with Tasmota firmware. The switches are controlled using Openhab Habpanel using an Android Tablet. Generally, this is my preferred way of  using the Android Tablet but the Arduino control panel is developed so that it can interface to external hardware at low cost. The control panel is developed using ESP-Link firmware with the El-client APIs and the hardware is an ESP8266 and Mega2560 combi board.  Besides acting as a touchscreen based on/off switch, it is also an internet clock (ntp) and a doorbell buzzer. The software/firmware/libraries are ESP-Link el-client APIs (interface to ESP-Link firmware MCUFriends Arduino library...

Next, I need a Micro P rocessing Unit (MPU), Micro-controller (MCU) and the software. After some design considerations, I have decided the brain of my system shall be a Raspberry PI. Raspberry is easily available. I have purchased mine at Taobao for less than S$70. It comes with a casing, power supply, 3xheat sinks, fan and a 16GB micro SD. This is the cheapest I can find. There are so many documentations, videos and websites on Raspberry Pi.  I watched a youtube clip showing Google Home assistant can be easily installed on a Pi. That sealed my decision to choose Raspberry Pi.  The next piece shall be the automation software, Currently, the most popular Home Automation control software are Openhab and HomeAssistant. I do not have time to evaluate both and settled for Openhab as I am more of a Java programmer. In case anything that needs debugging, it will be easier for me (but it turned out that I do not really need to look at the code). I like the Arduino ...