The Gertbot board works as either a stand-alone power controller connected to a computer via a serial link and controlled from Windows or as a plug-in to the Raspberry Pi environment. It has four channels each capable of driving 30 V at 2.5 A and can drive both capacitive and inductive loads. Besides four H-bridges the board also has two open drain N-MOSFETS which can sink 3 A at 30 V. The board is primarily targeted to drive stepper motors, brushed motors and other robotic hardware but it will be just as much at home controlling power in other applications. The outputs have short-circuit and thermal protection.

The board includes a 64 MHz ARM Cortex-M3 processor to take care of signal timing, leaving the computer free to work on other things. It can drive PWM signals from 10 Hz to 10 KHz and produces precise signals for stepper motors as slow as one step every 16 seconds up to 5000 steps per second. The board has limit switch inputs, handled locally to control motor travel. The system can be expanded to four boards giving control of eight stepper motors or 16 brushed motors. The boards can also be wired in parallel if more current is needed.

The accompanying software comes with full source code and includes a debug and control GUI running under Linux or Windows. It has C-drivers, Python drivers and numerous example programs. If Raspberry Pi is your thing don't forget our books for both beginners and more advanced users as well as the Raspberry Pi hardware we have on offer. The Elektor elves have been working overtime in the lab to make sure we don't run out before christmas, but dont leave it too late!