Arduino connected to Nexus S
Since Kristian’s release of SPP service for USB Host 2.0 library I got many e-mails with questions about Bluetooth serial communications in general and using the SPP class in particular. While establishing a Bluetooth connection is quite easy when using PCs/smartphones/tablets, the Arduino implementation is less user-friendly (for a good reason) and somewhat confusing. This article is intended to be a short tutorial of Arduino USB Bluetooth connectivity using an Android device as a peer – in my opinion, the simplest one to set up and communicate.
To follow this tutorial, you will need the following:
- An Arduino board ( I sell them too )
- full-size USB Host Shield 2.0
- USB Host Shield 2.0 library downloaded and installed in your Arduino library directory
- An SPP example sketch
- Bluetooth dongle – see below for detailed discussion
- Android device – a phone or tablet. The accuracy of this tutorial has been checked on Nexus S phone and Nexus 7 tablet, both running Jelly Bean 4.1.1 OS.
- A Bluetooth terminal emulator app for Android – I use Blueterm
The hardware setup is shown on the title photo (click on it to make it larger). It is a good idea to use external power supply at least in the beginning – some Bluetooth dongles are not happy when powered together with Arduino board/USB Host shield from USB cable. On a side note, it is always a good idea to use external power supply while experimenting with USB devices, especially when using current Arduino boards with their weak regulators. Also, Bluetooth code requires plenty of resources. The example used in this article compiles in ~24K and even though it would work on standard Arduino, any meaningful project will likely require a bigger board, like a Mega.
Continue reading Using USB Bluetooth dongle on Arduino to connect to Android phone