The PADI IoT Stamp module is a newly emerging alternative to the already well-known ESP8266, with much more interesting features.
Like almost all microcontrollers, PADI has general-purpose I / O pins (GPIO). They can be used for direct connection of sensors or other actuating devices, as well as for connecting several microcontrollers to the network using various interfaces displayed on the pins.
Modern microcontrollers and single-chip systems have many interfaces for communicating with peripheral devices. One of them, the easiest to implement - SPI or Serial Peripheral Interface - allows you to transfer data in two directions simultaneously over a single clock signal, that is, it is full-duplex.
The I2C interface, Inter-Integrated Circuit, was developed by Philips to connect devices within a single device. Now it is used everywhere for "communication" of the microcontroller and the periphery or equally equivalent controllers due to the small number of wires (2 in total) and relatively high speeds.
After analyzing the work with the most popular interface and PADI I / O ports, it is time to move on to the most complex and interesting - the integrated Wi-Fi wireless module.
The UART interface is one of the first external computer interfaces that was already used in the first self-assembled computers as a COM port (RS232, is still in use). It would be strange if PADI did not have at least one such interface, and it has as many as 3!