Microsoft Pocket PC to lock out non-ARM chips

Microsoft is turning its back on two of its current chip partners by limiting support in the next version of its Pocket PC operating system to just one supplier - UK-based ARM Holdings.

Pocket PCs running on the current generation of the operating system support processors from three different manufacturers - MIPS, SuperH and ARM.

However, the next generation of Microsoft's Pocket PC operating system - code-named Merlin - will only support processors produced by ARM Holdings.

Sources suggest that the next OS will see Microsoft abandon the multi-processor model in favour of a single processor support.

This decision is likely to reduce the amount of processor and memory resources consumed by the operating system, the so-called "footprint".

Microsoft has already been criticised for having too large a footprint on its mobile devices, and the Pocket PC has a much shorter battery life than many alternative devices, such as those made by Palm.

It will also simplify application development and OS upgrades.

Many Pocket PCs already use ARM processors, including the most popular range, the Compaq iPaq.

MIPS processors appear in Casio's Cassiopeia, as well as handheld devices from Philips, Samsung, Sharp and some other Compaq models such as the Aero.

Cores from SuperH, a joint venture between STMicroelectronics and Hitachi, are used in Hitachi products and the HP Jornada.

The news will come as a blow to MIPS and SuperH, but will not spell the end of their involvement in the market as both products are used in a range of other embedded applications.

Besides, Microsoft does not dominate the Pocket PC market in the same way as it dominates the desktop - Palm still has a larger share of the US market.

Microsoft declined to comment on the news.