On Fri, Oct 30, 2009 at 10:35 AM, Alan B. Pearce wrote: >>Being a digital input on the PIC, it shouldn't make a difference >>whether it is a generic input pin or an I2C input. Therefore, you >>would just look at the electrical characteristics charts at the end of >>the datasheet to find the min/max voltage thresholds for a digital >>input pin. > > But I believe the SMBus levels assume the use of 3V3 logic, so have lower > threshold levels than 'normal' 5V I2C levels (and this would be borne out by > the OPs quoted levels). I believe this is why the extra function is added. > It may not appear on 3V3 only PICs, I haven't checked. > Page 347 of the datasheet says that, with SMBus enabled, the thresholds are 0.8/2.1v. -- Martin K. -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist