XAPP979 (v1.0) February 26, 2007 www.xilinx.com 1© 2007 Xilinx, Inc. All rights reserved. All Xilinx trademarks, registered trademarks, patents, and further disclaimers are as listed at http://www.xilinx.com/legal.htm. PowerPC isa trademark of IBM Inc. All other trademarks and registered trademarks are the property of their respective owners. All specifications are subject to change without notice.NOTICE OF DISCLAIMER: Xilinx is providing this design, code, or information "as is." By providing the design, code, or information as one possible implementation of this feature,application, or standard, Xilinx makes no representation that this implementation is free from any claims of infringement. You are responsible for obtaining any rights you mayrequire for your implementation. Xilinx expressly disclaims any warranty whatsoever with respect to the adequacy of the implementation, including but not limited to any warrantiesor representations that this implementation is free from claims of infringement and any implied warranties of merchantability or fitness for a particular purpose.Summary This application note describes how to build a reference system for the On-Chip Peripheral BusInter IC (OPB IIC) core using the IBM PowerPC™ 405 Processor (PPC405) based embeddedsystem in the ML403 Embedded Development Platform. The reference system is Base SystemBuilder (BSB) based.An IIC primer is given and an OPB IIC register reference is provided. The Xilinx MicroprocessorDebugger (XMD) commands are used for verifying that the OPB IIC core operates correctly.Several software projects illustrate how to configure the OPB IIC core, set up interrupts, and doread and write operations. Some of the software projects interface the OPB IIC to theMicroChip 24LC04B serial EEPROM with an IIC interface, while others interface to theTotalPhase Aardvark Adapter, which provides IIC master and slave functionality. The procedurefor using ChipScope™ to analyze OPB IIC functionality is provided. The steps used to build aLinux kernel using MontaVista are listed. Simulation output files for analyzing basic IICtransactions are provided.IncludedSystemsThis application note includes one reference system:www.xilinx.com/bvdocs/appnotes/xapp979.zipThe project name used in xapp979.zip is ml403_ppc_opb_iic.RequiredHardware/ToolsUsers must have the following tools, cables, peripherals, and licenses available and installed:• Xilinx EDK 8.2.02i• Xilinx ISE 8.2.03• Xilinx Download Cable (Platform Cable USB or Parallel Cable IV)• Monta Vista Linux v2.4 Development Kit• Modeltech ModelSim v6.1d• ChipScope v8.2Application Note: Embedded ProcessingXAPP979 (v1.0) February 26, 2007Reference System: OPB IIC Using theML403 Evaluation PlatformAuthor: Paul Glover, Ed Meinelt, Lester SandersR