document.write("<FONT color=#ffff66><STRONG>The CtrlBox - An Ethernet Control System Interface<BR><\/STRONG><\/FONT><FONT color=#000000>by Ralph Stirling <\/FONT><BR>This well-designed motion control interface features a WIZnet W5100 that provides an interface between a Xilinx Spartan3 FPGA board and a host computer. The FPGA counts pulses from four quadrature shaft encoders and generates PWM for a motor amplifier. You can use the host PC to perform control calculations. Here the system is used in an inverted pendulum apparatus.<BR>\n<FORM method=post action=http:\/\/secure-nt3.localweb.com\/cgi-bin\/cart32.exe\/cellar-AddItem><INPUT id=PartNo value=Stirling-234 type=hidden name=PartNo> <INPUT id=Item value=single-article type=hidden name=Item> <INPUT id=Price value=2.00 type=hidden name=Price> <BR><FONT size=1 face=Arial><INPUT id=submit value=\"Purchase this Article\" type=submit name=submit> <\/FONT><\/FORM>");