DS2251T_06 Datasheet, PDF (1/22 Pages) Dallas Semiconductor – 128k Soft Microcontroller Module

DS2251T
128k Soft Microcontroller Module
www.maxim-ic.com
FEATURES
8051-Compatible Microcontroller Adapts
to Its Task
32, 64, or 128kbytes of Nonvolatile SRAM
for Program and/or Data Storage
In-System Programming via On-Chip Serial
Port
Capable of Modifying its Own Program or
Data Memory in the End System
Provides Separate Byte-Wide Bus for
Peripherals
Performs CRC-16 Check of NV RAM
Memory
High-Reliability Operation
Maintains All Nonvolatile Resources Up to
10 Years in the Absence of V_CC at Room
Temperature
Power-Fail Reset
Early Warning Power-fail Interrupt
Watchdog Timer
Lithium Backed Memory Remembers System
State
Precision Reference for Power Monitor
Fully 8051-Compatible
128 Bytes Scratchpad RAM
Two Timer/Counters
On-Chip Serial Port
32 Parallel I/O Port Pins
Permanently Powered Real-Time Clock
PIN CONFIGURATION
72-Pin SIMM
DESCRIPTION
The DS2251T 128k soft microcontroller module is an 8051-compatible microcontroller module based on
nonvolatile RAM technology. It is designed for systems that need large quantities of nonvolatile memory.
Like other members of the secure microcontroller family, it provides full compatibility with the 8051
instruction set, timers, serial port, and parallel I/O ports. By using NV RAM instead of ROM, the user can
program, then reprogram the microcontroller while in-system. The application software can even change
its own operation. This allows frequent software upgrades, adaptive programs, customized systems, etc.
In addition, by using NV RAM, the DS2251T is ideal for data logging applications. The powerful real-
time clock includes interrupts for time stamp and date. It keeps time to one-hundredth of seconds using its
on-board 32kHz crystal.
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REV: 061306