Arduino Relay Shield is an key element when you need to give actions to your projects. The BMini is the perfect match for that.
The BMini is an Arduino relay shield featured in the BieMme Store a couple of month ago. I think it is a great product and I’m very excited to tell you more about it.
Basically, it is a Relay Shield for Mini 05, Ethernet and UNO boards, specifically designed for home and industrial automation. You upload your sketch in the Arduino board, plug it in the BMini… that’s 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 panel 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 post I’d like to describe you a project I’m working on that consists of connecting an Android multi touch panel 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 Android multi touch panel I used is that it has many interfaces such as Ethernet, RS485, RS32 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 →
The bmANA is an essential product when reading from analog inputs with Arduino.
0-10V, NTC/PTC and 4-20ma Arduino Analog Inputs Converter
We are glad to present a simple but very powerful and flexible board that let you read different types of analog inputs. Now ready from our online store.
It is well known that in the home and (especially) in the industrial automation world the most used analog input types are 0-20ma/4-20ma (current), 0-10V (tension) or NTC/PTC thermocouples. Conversely, makers already know that the Arduino boards support 0-5V tension analog inputs only.
Based on these assumptions, we designed and created a new board that converts analog signals to 0-5V tension with 10-bit resolution. This will enhance spectrum of projects in which Arduino can be used.
The BmAna board has 4 analog inputs and each one can be set with one of the following measurement type:
Power supply: can be used either 5Vdc or 24Vdc for the most widespread use in every field of application.
To make easy and secure the connections with the measurement sources, we used terminal blocks.
Where and how can be used? This 0-10V, NTC/PTC and 4-20ma Arduino conversion board can be used for instance with our Bmini! Take for instance a flat cable with a RJ45 connector: plug it to the Bmini (through the J8 connector) and connect it to the bmAna. You have now expanded the functionalities of the Bmini and ready for reading almost all types of analog inputs currently used in the home and industrial automation sector.
Do you like this product? Just let us know!
In the following posts, we will present in more details the board features providing examples and technical specs.
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 →