I2C Protocol Analyzer - a Helpful tool, or overkill?
Interesting and Useful Links

http://www.nxp.com/acrobat_download2/literature/9398/39340011.pdf  -  The current official I2C bus protocol spec.

http://www.easyi2c.com  -  main site for the EasyI2C(TM) protocol analyzer

http://www.busi2c.com  -  case study of using an I2C protocol analyzer to troubleshoot a TV

http://www.i2cprotocol.com  -  basic overview of the I2C, TWI or SMBus protocol

http://www.analyzeri2c.com  -  how a protocol analyzer differs from a simple bus monitor

http://ezinearticles.com/?I2C-Protocol-Subtleties---Part-1&id=5012664 - a multi-part article series discussing some advanced I2C-related topics, especially what to watch out for when creating a new design that includes I2C.

http://ezinearticles.com/?I2C-Protocol-Subtleties,-Part-2:-Missing-START&id=6034071  - an in-depth discussion of START-related potential errors.

http://ezinearticles.com/?I2C-Protocol-Subtleties,-Part-3:-Missing-STOP&id=6477645 - an examination of possible STOP bit errors.

http://ezinearticles.com/?I2C-Protocol-Subtleties,-Part-4:-Unexpected-STOP&id=6489747 - more on STOP errors.
(Copyright 2011 Robert Fries; All rights reserved worldwide.)