The MSP430X is 100% compatible with the existing MSP430s allowing existing code libraries to be reused. The new MSP430X architecture is 100% compatible with the MSP430 architecture and allows 16x more memory addressing using less code and fewer cycles. Extended addressing modes are incorporated that allow the existing MSP430 instruction set to operate page-free throughout the entire 1MB memory model with improved code density using fewer clock cycles. Extended instructions designed for the large memory allow optimal high-level code density with full backward compatibility, making it possible to develop very sophisticated real-time applications completely in modular C libraries.