Measured Laser Temperature. For DWDM applications, the diagnostic interface report either laser wavelength or temperature, with a given module�s reporting defined by bit 1 of the object sfpConfigOptionalWdm. The value 0 means -128 Celsuis. An increment on one is equivalent to 1/256 degree, yielding a total range of -128 to +128 Celsius. Temperature accuracy is vendor specific but must be better than � 0.2 degrees Celsius over specified operating temperature and voltage.