Internet of Things and Smick
1. Internet of Things
Internet is the worldwide network of interconnected computers. The Internet was born in the 60s as a research project, but only in 1995 it was used for commercial purposes, thus opening up to the general public.
Today, in developed countries, most people are connected to the Internet, both from a fixed location and on the move, using PCs, tablets, smartphones or smart speakers (Alexa, Google Home, ...). They are sophisticated terminals with graphic, tactile and vocal interfaces.
The IoT aims to connect things to the Internet. Since things are much simpler than people, they do not need sophisticated terminals for connection, but smart transducers (see next module).
sophisticated cell phones to connect to the Internet, but smart transducers. A transducer is a sensor or an actuator.
A sensor transforms physical environmental quantities (stimuli) into electrical quantities. An actuator, on the other hand, transforms electrical quantities into physical quantities producing actions on the environment.
A smart transducer is a transducer with the ability to process, store and communicate.
Smick is the smart component of a smart transducer and realizes the physical interaction with the environment (physical computing) and symbolic interaction with the Internet (Internet computing).
Smick has 16 PINs to connect sensors and actuators, a Wi-Fi transceiver to connect to the Internet and a USB port for power supply and connection to a PC for programming.
3. Smick features
Smick has a RISC processor and a Wi-Fi transceiver. The 32-bit RISC processor has a clock frequency of 80/160 MHz and memory capacity of 64KB ROM, 160KB RAM and 4MB EEPROM.
The Wi-Fi transceiver uses the 2.4 GHz frequency and implements the IEEE 802.11b / g / n standards.
Smick has a micro USB interface for power supply and PC programming.
The 16 I / O PINs allow analogue, digital and serial connection (UART, I2C, SPI) of various transducers with 3.3V logic.
The Wi-Fi interface can be used to connect to the Internet (station mode), to accept connections from other Smick (Access Point mode) or to recognize the presence of friendly Wi-Fi devices (sniffing mode).
Smick Consumes less than one watt and 10 micro Amps in deep-sleep mode. It is small and light: it weighs 14 grams and its dimensions in millimeters are 39x32x16.
Smick use the following Internet services:
- NTP (Network Time Protocol) to update date and time;
- OTA (Over-The-Air) firmware upload;
- MQTT (Message Queue Telemetry Transport) for message exchange;
- VUI (Voice User Interface) to receive voice commands from Amazon Alexa and Google Home.
It is easy to program because it does not require computer skills, but common logical skills. Its K language interpreter allows you to build event-based control logics in a few simple steps. The K language is based on the normal logical-mathematical formalism learned at school (see the example in the slides).
The USB serial interface is used to program it by connecting to a PC or to power it via a power bank or a network transformer (5V).
The LED indicates the connection status to the Wi-Fi router (rapid flashing), to the MQTT or VUI services (slow flashing) or the operating status (flashing every 3 seconds).
The 16 I / O PINs are divided into: 3 power pins, a reset PIN, 2 PINs of the serial interface (UART), an analog input PIN and 9 digital I / O or PWM PINs.
A micro reset button is useful to restore the system in case of unexpected behavior.
The Wi-Fi interface is essential to connect to the Internet via a normal home Wi-Fi router connected to the fiber, a mobile Wi-Fi router with SIM or a common smart phone in tethering mode.