Intel LUPXA255A0C400: A Technical Overview of the PXA255 Processor for Embedded Applications
The Intel PXA255 processor, identified by the part number LUPXA255A0C400, stands as a significant milestone in the evolution of embedded and mobile computing. As a member of the Intel XScale microarchitecture family, this system-on-chip (SoC) was engineered to deliver a powerful blend of high performance and exceptional power efficiency, making it a cornerstone for a generation of sophisticated embedded devices.
At its core, the PXA255 is built around an Intel XScale core based on the ARMv5TE architecture, operating at frequencies up to 400 MHz. This RISC-based design provides a robust instruction set and high performance per clock cycle, enabling it to handle complex computational tasks efficiently. A key enhancement over its predecessor, the PXA250, is its separate memory bus for SDRAM and internal peripherals. This bifurcated bus architecture significantly reduces internal bus contention, leading to markedly improved overall system performance and more deterministic operation—a critical factor for real-time embedded applications.
The processor integrates a rich set of peripherals directly on-die, minimizing the need for external components and reducing total system cost and footprint. Its feature set includes:
Multi-port Memory Controller: Supporting various memory types including SDRAM, SRAM, and Flash.
LCD Controller: Providing direct support for passive (STN) and active (TFT) panels, enabling sharp graphical user interfaces.
Power Management Unit: Featuring multiple low-power modes (e.g., Idle, Standby, Sleep) that allow developers to finely tune power consumption based on operational requirements, which is vital for battery-powered devices.
Extensive Connectivity: Integrated controllers for USB client functionality, MM/SD memory cards, and a full suite of serial communications (I²C, I²S, UARTs).
The combination of its XScale performance and advanced power management made the PXA255 exceptionally well-suited for a diverse range of applications. It became the processor of choice for manufacturers of Personal Digital Assistants (PDAs), barcode scanners, point-of-sale (POS) terminals, industrial automation controls, and test and measurement equipment. Its ability to run operating systems such as Windows CE, Linux, and other real-time operating systems (RTOS) further expanded its versatility in the embedded market.
In summary, the Intel PXA255 processor represented a carefully balanced solution, offering a compelling mix of computational power, integrated features, and energy-conscious operation. It empowered a wave of innovative portable and embedded products that required more than what traditional microcontrollers could offer but did not need the full power—and power draw—of a desktop-grade CPU.
ICGOOODFIND: The Intel PXA255 (LUPXA255A0C400) is a quintessential example of a highly integrated, power-efficient application processor that successfully bridged the gap between microcontrollers and high-performance CPUs, leaving a lasting legacy in the history of embedded systems design.
Keywords: Intel XScale, ARMv5TE, Power Management, Embedded Applications, System-on-Chip (SoC)
