PLC programming, IEC 61131

Here you have a few links that may help you getting started with PLCs programming:

• Wikipedia, what else? http://en.wikipedia.org/wiki/IEC_61131-3
• www.plcopen.org introduction to the standard. www.plcopen.org/pages/pc2_training/downloads/downloads/new_intro_iec.doc
• Comparison of the different languages defined by the standard: www.automation.com/pdf_articles/IEC_Programming_Thayer_L.pdf
• Great online book: http://engineeronadisk.com/V2/book_PLC/engineeronadisk.html
  

Enjoy!!