The Uno board has 14 digital input/output pins – with six that can be used as PWM outputs – and six analogue inputs. Other features include a 16MHz ceramic resonator, USB connection, an ICSP header, ...
Connector to add external battery to real-time clock (RTC) inside Renesas MCU (MCU RTC power pad held to 5V rail on Minima) Secondary (wireless) processor: 240MHz 3.3V dual core 32bit Espressif ...