DESCRIPTION
The DS5000(T) Soft Microcontroller Module is a fully 8051-compatible 8-bit CMOS microcontroller that offers “softness” in all aspects of its application. This is accomplished through the comprehensive use of nonvolatile technology to preserve all information in the absence of system VCC. The internal program/data memory space is implemented using either 8 or 32 kbytes of nonvolatile CMOS SRAM. Furthermore, internal data registers and key configuration registers are also nonvolatile. An optional realtime clock (RTC) gives permanently powered timekeeping. The clock keeps time to a hundredth of a second using an on-board crystal.

FEATURES
■ 8-Bit 8051-Compatible Microcontroller
   Adapts to Task at Hand 8 or 32 kbytes of Nonvolatile RAM for Program and/or Data Memory Storage
   Initial Downloading of Software in End System via On-Chip Serial Port
   Capable of Modifying Its Own Program and/or Data Memory in End Use
■ Crashproof Operation
   Maintains All Nonvolatile Resources for 10 Years in the Absence of VCC at Room Temperature
   Power-Fail Reset Early Warning Power-Fail Interrupt Watchdog Timer
■ Software Security Feature
   Executes Encrypted Software to Prevent
   Unauthorized Disclosure
■ On-Chip, Full-Duplex Serial I/O Ports
■ Two On-Chip Timer/Event Counters
■ 32 Parallel I/O Lines
■ Compatible with Industry Standard 8051 Instruction Set and Pinout
■ Optional Permanently Powered Real-Time Clock (DS5000T)