| 128 kbytes of user NV RAM Integrated NV SRAM, real-time clock, crystal, power-fail control circuit and lithium energy source Totally nonvolatile with over 10 years of operation in the absence of power Watchdog timer restarts an out-of-control processor Alarm function schedules real-time related activities such as system wakeup Programmable interrupts and square wave output All registers are individually addressable via the address and data bus Interrupt signals active in power-down mode |