Yes, those pull-ups are necessary. The I2C interface pins on a microcontroller (or on the slave device) are open-collector.
-Adam On Sun, Apr 15, 2012 at 9:50 AM, Quixotic Nixotic <nixci...@jsdesign.co.uk>wrote: > I am driving a DS3231 I2C clock from a PIC's pins. If the logic state of > the pins is always high or low, do I really need pullups on the bus? The > only reason I ask is that space is at a premium. > > -- > You received this message because you are subscribed to the Google Groups > "neonixie-l" group. > To view this discussion on the web, visit > https://groups.google.com/d/msg/neonixie-l/-/hF9vShAcTecJ. > To post to this group, send an email to neonixie-l@googlegroups.com. > To unsubscribe from this group, send email to > neonixie-l+unsubscr...@googlegroups.com. > For more options, visit this group at > http://groups.google.com/group/neonixie-l?hl=en-GB. > -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To post to this group, send an email to neonixie-l@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
