Converging Needs Drive Storage Interface Standard

By Cheryl Ajluni

Disk drives have increasingly found their way into handheld consumer electronics applications. However, existing disk drive interfaces built around desktop PCs and large storage device applications are unsuitable for next-generation devices like mobile handsets and audio/video players. This lack of a disk drive interface tailored to the emerging market needs has left a void in the industry that is now being filled.

The electronics industry is constantly being bombarded with new and changing standards and specifications. Some specifications achieve standardization and make their way to market, while others fade quietly into obscurity. Regardless, the process of developing a standard is often a long and arduous one. It’s not so amazing, then, that a specification for the storage interface for next-generation handhelds and portable consumer electronics devices has recently been announced. What is surprising is that this announcement comes a mere 6 months after the organization charged with its creation was announced.

The Consumer Electronics - Advanced Technology Attachment (CE-ATA) Working Group was officially launched in September 2004 with the goal of developing a storage interface standard for mini-hard drives. The standard, the CE-ATA Digital Protocol Version 1.0 Handheld/PDA Storage Interface specification, was released in March 2005 at the Intel Developer Forum (IDF). A community of prominent companies in the small form factor disk drive and handheld consumer market segments, known as the CE-ATA Promoter Group, is backing the standard. The Promoter Group’s founding members include Hitachi Global Storage Technologies, Intel Corporation, Marvell Semiconductor, Nokia Corporation, Seagate Technology and Toshiba America Information Systems. To date, the Working Group has over 45 member companies.

One reason why the CE-ATA organization may have moved so quickly is that each member company is driven by the same need: profit. Adoption of this specification is expected to lower development costs and speed time-to-market for consumer electronic devices. Using a common interface, as opposed to multiple proprietary solutions, offers participating companies the ability to address requirements inherent in handheld and consumer electronics applications like low pin count, low voltage, power efficiency, cost effectiveness and integration efficiency. At the same time, a common standard enables the creation of a larger market for all vendors.

The CE-ATA specification defines a physical and logical interface between a storage device and a host. The interface is optimized for mobile power and performance, scalable for future usage models, and consistent with AT attachment software infrastructure. It also ensures compatibility between host and storage devices. Specific applications that this specification targets include portable music and video players, smartphones, digital video and still cameras, personal digital assistants (PDAs) and external storage devices. End products supporting the new technology are expected to be available by the end of 2005.

When the Working Group released the CE-ATA protocol specification at IDF it highlighted the announcement with a series of demonstrations to illustrate the specification’s viability. One demonstration consisted of a prototype handheld media player from Intel running video off a CE-ATA prototype disk drive. The CE-ATA prototype drive, supplied by Marvell, was an off-the-shelf, 1.8-inch hard drive configured with Marvell’s chipset and firmware. The hard drive featured the 88i6310 System-on-Chip (SoC), as well as Marvell’s stacked flash, motor controller, switching regulator and preamplifier. The host system in the demonstration (see Figure 1) was an Intel development board for a PDA-style handheld. It featured an Intel® PXA270 processor running Intel’s prototype host driver software.

Figure 1. An Intel PXA270 processor was the host for a demonstration of the CE-ATA standard that ran video from a hard disk onto a PDA handheld. As the first Intel XScale® technology-based processor to include Intel® Wireless MMX technology, the processor enables high-performance multimedia acceleration while offering an industry proven instruction set.

A second demonstration, conducted by Marvell and Hitachi Global Storage Technologies, was designed to highlight key CE-ATA interface fundamentals. It illustrated the capabilities of CE-ATA technology on a prototype PDA platform that played video stored on a Hitachi Travelstar 1.8-inch hard disk drive (see Figure 2). As with the other disk drive, the Travelstar product in this demonstration was reconfigured with Marvell’s chipset and firmware.

Figure 2. Disk drives such as the Hitachi Travelstar offer the small footprint and light-weight design that can accommodate ultra-portable, handheld devices. Adapting them to the CE-ATA standard provides for more flexible integration.

Backers hope that the CE-ATA specification will quickly become the disk drive interface of choice in the handheld and consumer electronic market segments. Its adoption will clearly bring with it a number of key benefits. Small form factor disk drive suppliers will be able to take advantage of a storage interface tailored to the needs of such devices, resulting in highly optimized disk drive designs. Host silicon providers and product integrators will benefit from the improved integration that the tailored interface affords due to its low pin count, favorable voltages and efficient protocol. For consumers, a disk drive interface tailored to the needs of the handheld and portable consumer market segments could spur storage use in innovative new products. Subsequently, it may lead to the development of products with a more efficient storage solution.

To further bolster the specification’s viability, the CE-ATA Promoter Group recently formed a formal liaison with the MultiMediaCard Association (MMCA). This arrangement aims at ensuring faster time-to-market and interoperability of disk drive solutions on small portable consumer devices. Under the terms of the agreement, the two groups will collaborate to ensure that the technologies they support are complimentary and address the needs of the storage industry in providing an interface that is ideally suited to portable consumer applications.

Toward that end, the MultiMediaCard (MMC) electrical interface now supports the CE-ATA specification using a protocol that employs existing MMC access primitives. The interface electrical and signaling definition is as defined in the MMC reference. CE-ATA referenced standards include MMC System Specification 4.0, MMC Systems Summary Specification 3.31, and AT Attachment with Packet Interface.

With its industry support and track record for staying ahead of schedule, the CE-ATA specification is well on its way to standardization. Designers with a need for mass storage in their handheld and portable units should become familiar with it. For more information on the CE-ATA initiative and its member companies, or to download the specification, go to

Cheryl Ajluni is the owner of Custom Media Solutions, specializing in technology-based content for publications and tradeshows. She has over 10 years experience covering the high-tech industry for such publications as Electronic Design and Embedded Systems Development and served as Editor in Chief of Wireless Systems Design. She has also worked in various engineering roles, holds a patent for the development of a solar cell detection system, and has a Bachelor of Science degree in physics and mathematics from the University of California, Davis.