The DS5001FP 128k Soft Microprocessor Chip is an 8051-compatible Secure Microcontroller family, which is based on nonvolatile RAM rather than ROM.Dallas' "soft" microprocessors can be programmed after installation in a system, which facilitates frequent software upgrades, adaptive programs, customized systems, etc. The user-set program and data partitions can also be modified to optimize reprogramming.Dallas' nonvolatile CMOS technology sets the standard for low-power consumption. With a user-supplied lithium battery, the on-chip power management circuitry can maintain all nonvolatile resources for greater than 10 years in the absence of external power.DS5001FP also provides crashproof operation in portable systems by saving the operating state and providing a power-fail reset, power-fail interrupt, and watchdog timer.The DS5001FP is intended for applications requiring large memory addressing. It includes bank switching that, with a little extra logic, enable it to address 252kbytes of data memory. The DS5001FP is available in a module that includes the RAM, a lithium cell and real-time clock (see the DS2251).The DS5001FP is ideal for data logging applications that require large, nonvolatile memory storage. It easily connects to a Dallas real-time clock to add nonvolatile, time-stamped data entry.Note: Designers must have the following documents to fully use all the features of this device. This data sheet contains pin descriptions, feature overviews, and electrical specifications. Errata sheets contain deviations from published specifications. The user's guides offer detailed information about device features and operation.