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Prototyping board supports direct 8- to 32-bit MCU upgrade

Engineers contemplating moving from 8-bit to 32-bit microcontroller systems now have a new option in the shape of Freescale’s Flexis MCU chips. The two parts released to introduce the Flexis range are, respectively, 8- and 32-bit devices that are not only software- and peripheral-compatible, but pin-for-pin compatible to permit a direct upgrade. MC9S08QE128 is the 8-bit part, and MCF51QE128 the 32-bit, Coldfire architecture, chip. Software you write for the 8-bit part will run unmodified on the 32-bit one.

The Crossbow development board from distributor Future Electronics supports the Freescale parts at launch. Crossbow conforms to the company’s Future-Blox format: Future-Blox is a standardised mechanical and electrical design that the distributor created to promote easy adoption of products it supplies from a variety of manufacturers. Future-Blox boards host active devices in a range of typical confi gurations in a stackable interconnection format, allowing you to rapidly prototype a complete system. Boards previously released include Ethernet embedded controllers, a brushless dc motor controller board, an ac induction motor controllerboard and a DSP board.

Crossbow extends the concept in that it provides a development environment for the new Freescale parts—and other MCUs that Freescale yet has to announce that will not be part of the Flexis range—in an interchangeable format. The MCUitself is mounted on a small “mezzanine” board that plugsonto the main pcb. You can, thecompany says, design a completesystem using the 8-bitpart, and simply plug in the corresponding32-bit chip to evaluatethe effect of the more powerfulchip in your system. Futuresupplies a special free editionof CodeWarrior tools with theCrossbow board. Features includeCAN 2.0B and USB 2.0interfaces, LCD driver ports, I2Cand SCI buses, 8-channel ADC,sockets for the ConnectBlueBluetooth module, FreescaleZigBee module and MaxstreamZigBee module.

As with other Future-Blox boards, Crossbow will be available free of charge to qualifying developers—which, the company says, means anyone who can demonstrate a likely reasonable usage of the parts they host. Future also issues full manufacturing descriptions of the boards; although the company intends them explicitly as development and prototyping vehicles, it says it has already seen users adopt the board designs with minimal modifi cations for shortproduction runs.

1. Future Electronics, www.futureelectronics.com.
2. Freescale, www. freescale.com.