Back. I did some checking, testing, etc, and reailzed I failed with =20 my original question -- I do need SCL pullups, but the reason I did =20 not have it in the 16F877A circuit was that I forgot that I had =20 bit-banged that (~6 years ago) on two regular I/O pins. The SCL line =20 went to logic high or low (never floating). On that, the SDA line had =20 a 3.9k pullup, and I frankly don't remember how I calculated it. That =20 controlled a single serial EEPROM at a very low speed. Ran a quick test using the actual MSSP module now, and used a very =20 high 10Mohm pull-down (to verify whether I really needed a pullup up =20 or not, by ensuring that if it floats, it would get pulled to ground), =20 and it did not work. Adding a 3.9k the pullup solved it. The spec is great, and answers my question. Thanks. Cheers, -Neil. Quoting Vicent Colomar Prats : > Sphero, thank you for that contribution. > > I did not know about that manual, specially second from NXP. I like it, i= s > very well explained and, think, is easy to understand. > > Greetings. > > > 2011/1/14 Spehro Pefhany > >> At 10:31 AM 14/01/2011, you wrote: >> >> > Okay. Whatever. But these are the specs I've come to know and use >> >ocassionally. >> >> >> >> Here are some more actual specs: >> >> http://www.nxp.com/acrobat_download2/literature/9398/39340011.pdf >> http://www.nxp.com/documents/user_manual/UM10204.pdf >> >> >> >> >Best regards, >> >> Spehro Pefhany --"it's the network..." "The Journey is the >> reward" >> speff@interlog.com Info for manufacturers: >> http://www.trexon.com >> Embedded software/hardware/analog Info for designers: >> http://www.speff.com >> >> > -- > http://www.piclist.com PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .