XScale is Intel's implementation of the fifth generation of the ARM architecture based on the ARM instruction set V5TE without floating point instructions. The XScale processor family belongs to the group of RISC architectures. It is used primarily in PDAs, in portable DVD players and in the embedded space application.

  • 4.1 Sale of division


In the context of a dispute between Intel and the semiconductor division of DEC Intel took over as a side effect rights to the ARM architecture as well as their StrongARM microcontroller line. For Intel, it was first to replace ( i860 and i960 ) their collapse in the paragraph rule of not more contemporary RISC processors. The later created XScale term describes nothing more than Intel's continuation of processors and controllers of the ARM line.

XScale families

There are four generations of XScale processors: PXA210/PXA25x, PXA26x, PXA27x, and PXA3xx.

Common features of all XScale processors

All generations of XScale are 32- bit ARM V5TE processors that are made ​​with a 0.18 - micron process, and have a 32 -KB data cache and a 32KB instruction cache. In addition, all have a 2 KB mini - data cache.


The PXA210 was Intel's entry-level XScale, which was designed for mobile applications. He came simultaneously with the PXA250 in February 2002 on the market and was available with 133 or 200 MHz.


The PXA25x family consists of the PXA250 and PXA255.

The PXA250 was Intel's first generation of XScale processors. It gave him three clock rates: 200 MHz, 300 MHz and 400 MHz. He came out in the chip version A in February 2002. But even the second version B was afflicted with various errors that had to be corrected with expensive fixes in the software.

The PXA255 came out in March 2003 as a replacement of its predecessor and was planned as a chip version C of the PXA250. The main difference was a doubled - speed internal bus ( 100 MHz to 200 MHz), for faster data interchange and a lower operating voltage ( 1.3 V only at 400 MHz) for reducing power consumption.


The PXA26x family consists of the PXA260 and PXA261 - PXA263.

The PXA260 is a stand-alone processor with the same clock rate as the PXA25x, but the casing is smaller by 53%.

The PXA261 - PXA263 are identical to the PXA260 but have additional internal memory in the processor. 16 MB 16 -bit StrataFlash memory in the PXA261, 32 MB 16 -bit StrataFlash memory in the PXA262 and 32MB 32 -bit StrataFlash memory in the PXA263. The PXA26x family was released in March 2003.

PXA27x ( Bulverde )

The PXA27x family ( code-named Bulverde ) consists of the PXA270 and PXA271 - PXA272 processors.

The PXA270 is available in four different clock rates (312 MHz, 416 MHz, 520 MHz and 624 MHz) and is a stand -alone processor without integrated memory.

The PXA271 can have four different clock rates ( 13 MHz, 104 MHz, 208 MHz and 416 MHz) and has 32 ​​MB 16 -bit StrataFlash memory and 32 MB 16-bit SDRAM in the same housing.

The PXA272 can be clocked at 312 MHz, 416 MHz or 520 MHz and has a built-in 64 MB 32 -bit StrataFlash memory.

Intel has added several new features in the PXA27x family:

  • Wireless SpeedStep: the processor is clocked down automatically depending on the computation load to save power.
  • Wireless MMX: 43 new SIMD instructions containing the full MMX instruction set and the integer instructions from Intel's SSE instruction set along with some commands that are unique to the XScale. They are used to increase the speed of encoding and decoding of multimedia as well as in games.

The PXA27x family was launched in April 2004. Together with the PXA27x family Intel has released the 2700G embedded graphics coprocessor.

PXA3xx ( Monahans )

In August 2005, Intel introduced the successor to the Bulverde PXA270 processor, codenamed Monahans. The new Monahans processor operating at 1.25GHz. Intel gave a performance improvement of 25 % compared to the Bulverde processor at (800 MIPS for the 624 MHz PXA270 processor compared to 1000 MIPS for the 1.25 GHz Monahans ). The successor to the 2700G graphics processor, codenamed Stanwood was discontinued by Intel. Some characteristics of the Stanwood - GPU are already integrated in the Monahans processor. In need for additional graphics functionality Intel recommends the use of third-party products, such as the Nvidia chip family GoForce.

Since November 2006, the processors of the PXA3xx series Marvell Semiconductors are commercially available.


With XScale processors are currently up to 128 MB of StrataFlash memory specially developed by Intel for mobile use directly addressable. An SDRAM up to 256 MB can be controlled ( the PXA270 up to 1 GB ). In addition, 64 MB of address space for slow I / O devices or fast SRAM are still available, this address space can be connected at the expense of Flash are increased ( in 32- MB increments).

Applications of the XScale

The XScale microprocessor is used in many PDAs, like the Palm Tungsten C or the Dell Axim X50 and X51. In addition, the XScale in portable media players ( portable video players ) is used as the Zen.

Some companies offer modular type systems or single-board computer (SBC ) with processors this family and make the architecture thus also useful for industrial applications. These companies usually offer also CPU modules for evaluation (short EVMs ) and Board Support Packages ( BSPs ) with application examples in order to facilitate the potential customers into the development of their own solutions.

Sale of business unit

On 27 June 2006, Intel announced the sale of its communications and application processor business to Marvell Technology Group for converted at the time of the sale 476 million euros (600 million U.S. dollars) known. After the contracted five -month transition period has now ended, Marvell has now unveiled the next generation of processors. The new generation PXA3xx is therefore no longer manufactured by Intel.