8051 Core
Introduction
The CPU used by Duo contains an 8051 core. The 8051 subsystem is located in a module that is independently powered by the RTC. The subsystem is configured with an 8051, an I2C/UART/SPI NOR/SD controller, a Timer/WDT, interrupt management, and a Mailbox IP. The system software can use the 8051 to manage wake-up conditions and wake up the system while it is in sleep mode, and communicate with external devices through peripheral controllers.