CAST 80251 Processor IP Core Runs Legacy and New Code Up to 24x Faster

Woodcliff Lake, NJ — June 08, 2010


The R80251XC core has been discontinued. Please contact Sales to learn more.

Electronic designers using the popular 8051 microcontroller can now apply their investment in 8051 knowledge and code to faster systems using the R80251XC IP core from semiconductor intellectual property (IP) provider CAST, Inc.

This core makes new chip design more economical by enabling the use of legacy application code with a modern, faster processor. The core is compatible with Intel MCS® 51 and MCS® 251 instruction set code, but can run twenty-four times faster than Intel’s original 8051 microcontroller chip and four times faster than the later 80C251. This preservation of 8051-based features with the better performance required for new features helps extend the useful lifetime of existing 8051-based systems, avoiding the expensive and risky transition to an entirely new architecture.

Developed by partner Evatronix SA, the R80251XC joins CAST’s extensive 8051-compatible IP product line and incorporates improvements developed over thirteen years. For example, user configurability helps lower gate counts and reduce power requirements by letting designers tailor the processor to a specific application: peripheral options include multiple UARTs, I2C interfaces, timers, and serial ports, single SPI, Watchdog, software reset and real-time clock modules.

The core uses a 32-bit internal architecture (ALU) for faster performance. Customers may choose between two versions of the core’s CPU: one has internal instruction set execution timing identical to the standard Intel 80C251 chip for the greatest compatibility, the other reduces execution timing by a factor of four for the greatest performance (four times the original chip).

Application development is facilitated with an optional on-board debugging package that is compatible with the widely popular KEIL µVision4 integrated development environment (IDE).

Learn more about CAST, Inc. and the R80251XC processor core by calling +1 201.391.8300 or visiting


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