We would like to thank you all the people that every day wrote us and that are following your innovative projects. We are working hard on developing new products for smart home and industrial automation. We are confident that they will surprise you! Stay tuned!
In this post, I’d like to share with you a video preview of the latest single board computer (SBC) with Android OS that I’m working on. It has a capacitive 7″ touch screen. Compared to the MCU ARM used in a previous home automation project, this SBC is shipped with an ARM Cortex A8 MCU at 1 GHz and with no doubt it is very powerful and fast.
In addition to Android (up to ver 4), it supports WinCE and Ubuntu. It has 512MB DDR2 on board SDRAM, 4GB of iNand flash memory, Ethernet, serial ports (3x Rs232, Rs485, uart, i2c, spi) and 4x USB Hosts, HDMI and TV OUT, 2x SD, G-sensor, GPS and GPRS interfaces and many more. For those of you interested to use this ARM Cortex in industrial automation, I designed a native Android library that manage the rs485 modbus protocol.
Take a look at the complete technical specifications. I’m working to share the Android projects I used for smart homes and industrial automation. If you find it interesting and you think that it could be a valid solution to your needs, please consider to buy it
In my home automation project with Arduino and Android I always paid special attention to communication failures. These might happens for many reasons and the system has to deal with them.
In particular, in the following video I was interested to show you some test I made in order to assess whether the information presented by the touchscreen monitor will be displayed whenever available.
The red led indicates that the Arduino is processing a modbus request. As you can see, it stops blinking when the bus 485 is interrupted and immediately after the connection has been restored, it restart to work. Indeed, take look at the bulb icons in the monitor. When the bus is restored, the bulb status will be updated.
In this brief Android development tutorial, you’ll be able to create your first Android Hello World application. The Android app that you’ll create can be installed in every Android smartphones, tables and especially in the newest development boards that are used in home and industrial applications.
First, you need to download Eclipse IDE. Since in the Download page many version are available, the one called “Eclipse IDE for Java Developers” should be fine.
Another important package to download is the Android SDK.
It is now time to present how to write an Android project that acts as a master and communicates with slave devices.
The nice thing of this design is that the logic that controls the smart home system is not constrained to be on the masters’ node. Instead, it can be distributed across all the Arduino devices. Indeed, since rs485 and modbus protocol were designed for industrial environments, this project could be easily used in industrial automation. Continue reading →
In this post I’d like to describe you a project I’m working on that consists of connecting an Android touch screen to one (or more) Arduino slave(s) using modbus protocol and rs485.
Even though the idea of this project could be applied in many fields, I chose to contextualize it in a typical smart home context: a touch display that dims lights, shows temperatures and bulbs statuses.
The nice feature of the single board PC with touch screen I used is that it has many interfaces such as Ethernet, rs485, rs232 and I²C as well.
I expressly selected rs485 because Arduino-based microcontrollers are not ready for Ethernet yet (even though some examples still exist but without great success). Indeed, rs485 is a well known standard that has been widely used in the industrial context and in building automation applications. It is a half-duplex, 2-wires, low noise bus that allows high speeds and remote devices connection (up to 1200 meters).
Furthermore, modbus is a serial communication protocol, developed for industrial applications, open and easy to deploy and maintain. I used modbus RTU, but other variations of the protocol still exist though. Continue reading →
We designed and developed a control system that uses our new board with Android operating system and a 7″ capacitive touch screen (figure on the right). It is connected to a pool of Arduino’s slaves over rs485 channel. Our tests suggest that the most efficient and lightweight communication protocol is the modbus. It works greatly also on Arduino devices. Indeed, we used Maxim’s max485 chip in order to convert Arduino TTL serial signal to rs485. Terminator resistor (120 Ohm) is connected accross the two wires to limit data corruption. Continue reading →