An overall experimental set-up for PACE experiments based on the omega machine concept is shown in the upper section "Programmable microscope system". Making experimental apparatuses portable is a challenge in itself. Due to budgetary reasons the researchers have to continue their use of their own valuable equipment for such a setup: pumps, microscope, camera and temperature-facilities are different in each lab encountered. Integrated solutions as we envisage have to design special interface for each of these devices. As a compromise, it turned out that beside a PC a relatively cheap controller-box would offer the best price-value-ratio pos-sible. Due to new developments in the electronics market, the controller-box Bio@Fox we built, shown in the lower images, has a 100 MHz micro-controller combined with two USB-connectors, three possible serial-interfaces (RS232), an Ethernet-PHY at 100 Mbit/s, sufficient amount of memory and a fully-fledged Linux-operating system plus about 20 user-programmable free I/Os.
Bio@Fox features at a glance:
- 3 x Pt-1000 temperature-sensor inputs
- 3 x A/D converters
- 3 x power H-bridges for temperature-control
- 2 x USB-ports and 3 x RS232 interfaces
- more than 40 individually controllable digital I/Os with at least five different I/O standards
- remote control via Ethernet interface
Our controller-box now combines this micro-controller (FOX-ET100LX) with a standard Spartan-3 FPGA from Xilinx (XC3S100ETQ144) and provides the necessary real time-capabilities plus a multitude of further user-programmable customized I/Os.
These two major ingredients are upgraded by 6 high-precision analogue sensory inputs (three of them are dedicated for temperature-measurements) and three galvanically decoupled power-switches with 5 Amps load-capacity each to drive two Peltier-elements plus a fan for cooling. Of course the I/Os needed for driving the Chemical microprocessor (ChµP) or a much simpler chip without any further control-ling logic devices are provided as well. Especially for these most simple chips five different computer-controllable driving voltages are available (from 1.2 V towards 3.3 V). The controller-box has two power-input-lines, one for the control-devices and a separate one for the power-switches.
The following hardware devices are currently supported: High performance pumps from Micro-Machining-Technology, as well as standard TSE-pumps both controlled via serial-interfaces (if the computer-hardware supports several hardwired serial-interfaces these can be used instead of the default USB-bus interfaces provided via USB-serial-adapters). The EMCCD-camera from Andor is supported as well as the firewire 1394-camera from Vosskuehler, of course the old FPGA-based control via the MereGen board is still available. The ng_biopro-software is running on Linux-PCs as well as on MacOSX-operating systems via X11. Priority was given to allow for an easy development of new drivers.