Designers contemplating a project based on the increasingly-popular ARM Cortex-A8 processor core have a unique resource to turn to for help with the design. A volunteer group called BeagleBoard.org has established an open-source effort that has made available a low-cost development platform based on a Texas Instruments (TI) OMAP processor that integrates a Cortex-A8 core. Design teams will find both hardware and software help at BeagleBoard.org, and the assistance applies whether the team is using a TI IC or another Cortex-A8-based IC. And while Cortex-A8-based ICs fall at the upper end of what may be called a microcontroller (MCU), design teams that typically rely on MCUs may find Cortex-A8-based ICs superior from a cost/performance perspective, especially if the application at hand involves multimedia.
The idea behind the BeagleBoard effort very much mirrors the open-source movements associated with the Linux and GNU communities. But while those efforts were primarily IT centric, BeagleBoard squarely targets embedded developers that might be working on anything from a video phone to a TV web platform to a home-automation system. Design teams are encouraged to use the software contributed to the community and to register their projects and share the fruits of their labor.
Also unlike the pure open-source software community, the BeagleBoard community includes a hardware aspect. You can buy low-cost development boards that accelerate a project both in terms of providing a ready-to-use software development platform, and the community allows design teams to reuse the development-board hardware design. Teams can download all of the PCB design materials including schematic, layout, and assembly designs.
The BeagleBoard community launched with the release of a board that’s based on a TI OMAP3530 processor. The Rev C release of that board is still available and the price has been dropped to $125. Teams can buy the board from Hotenda and other sources. The new release includes a 720-MHz processor, 2 Gbytes of DRAM, and 2 Gbytes of flash. The OMAP processor also includes what TI calls an Image/Video/Audio Accelerator Subsystem that is based on a 520-MHz TMS320C54X DSP core.
The idea behind the BeagleBoard development board was decidedly minimalist. The community that designed the board didn’t add many features beyond those integrated in the OMAP processor. The processor includes multimedia support so the design team simply brought those audio and video interfaces to connectors and left the addition of other peripherals up to the design team. The board is powered from a USB cable from a PC development host. That minimalist philosophy makes the board very affordable.
The community has begun to grow and inevitably there is an evolution in the hardware platform just as there is in software in communities such as Linux. In the case of BeagleBoard, the hardware and software will advance concurrently. Hotenda and others are now selling the BeagleBoard-XM platform that includes a faster processor than does the original design. The Cortex-A8 core runs at 1 GHz on the new board and the DSP core clock has been increased to 800 MHz. The new board sells for $149.
TI has also announced their collaboration with Mistral Solutions on the CraneBoard. That board integrates an AM35x Sitara processor that’s also based on the Cortex-A8, but that doesn’t integrate a DSP core. The board includes a 600-MHz processor, 256 Mbytes of DRAM and 256 Mbytes of flash.
Design teams working with the CraneBoard will find development help from multiple open-source resources. The board is compatible with the resources offered at BeagleBoard.org – obviously with the exception that it can not utilize code developed for the C64x DSP. And the CraneBoard.org site offers an open-source, board-support package for Linux. Hotenda also offers the CraneBoard.
To gauge what can be accomplished with the BeagleBoard and similar platforms, consider example applications that have been posted on the community web site. Community members have ported the Android, Symbian, and QNX Neutrino operating systems to the platform. There is even a Windows Embedded port.
The community has also yielded a number of third-party hardware support products. For example, you can find a number of daughter cards on the third-party resources page and even different-but-compatible versions of the BeagleBoard functionality. Also, distributors such as Hotenda offer a large selection of support products. For example, the Hotenda BeagleBoard-XM page lists USB touchscreens, memory-card readers, cables of all types, and more.