IoT for the smarter home : Page 3 of 4

May 11, 2016 //By Pushek Madaan and Gagan Luthra
The advent of Bluetooth Low Energy (BLE) has revolutionized the concept of the Internet of Things (IoT) and has helped take it from concept to commercial reality. The biggest reason for the proliferation of BLE has been its presence in smartphones, tablets and off-late, laptops too.
Figure 2 shows a high-level BLE mesh implementation for the smart home system.

Figure 2: BLE interface.


Dynamically Changing BLE GAP Roles: In this application, all nodes operate as GAP Peripherals (slaves) and try to establish a BLE connection with the GAP Central (master). Once a node receives control information from the GAP Central or it detects motion from the PIR sensors, it changes its role to a GAP Central and establishes connections with the other nodes in the system to forward the information onwards. By doing so, the other nodes do not need direct control information from the mobile phone, but instead can receive this same information from a nearby node.

Due to the wide range of functionalities required in this application, one would typically need a multi-chip solution. Using multiple chips not only increases the BOM cost but also increases the PCB size, which is critical for space-constrained applications such as these. Cypress’ PSoC 4 BLE solution is a perfect fit for such applications. This solution provides BLE communication, which can not only work as both the GAP Peripheral and GAP Central, but also dynamically switch between the two GAP roles. Additionally, PSoC 4 BLE includes programmable analog blocks to create custom sensor interfaces and programmable digital blocks to implement control units – all of which can be used to design a true single-chip solution. This approach provides an economical solution by integrating the BOM and reducing PCB size, while also providing modularity by using the same chip to implement different functionalities for different nodes.

Design category: