Hi Steven, See my comments below.
On Monday, June 29, 2015 at 9:28:17 PM UTC+2, Steven Saunderson wrote: > > Hi Ivan, > > Thanks fo all your work here. I'll try to remove the caps from my > Cubieboard2 tonight and see if that makes any difference. > Awaiting for results :) > > Your RTC battery consumption sounds okay. I'll compare mine. If > excessive I could fit a more expensive rechargeable battery instead. > Yes, sounds ok, but should probably be even less (DS1307 takes 500nA or similar). However, this is just fine for me. > > Are you seeing AC noise on both legs of your crystal ? One thing that > surprised me is that one leg of mine is at 1.3V which doesn't sound right. > Also, if I read the LOSC_CTRL_REG on the Cubieboard2 I always get 0x2009 > whereas on other A20 boards I always get 0x0009. The 0x2000 bit is > undocumented. > Hmm, I have to take a scope and check - will do it later today. As I said, funny thing is that I can only see real oscillations on Banana Pi, all the other boards have 0.4V on one leg and 1.3V on the other. Some small noise is visible, yes, but nothing too drastic. I'll try to make some photos and record some data today and post back. > > I note your earlier comment that RTCVDD should be only 1.3V. This is > minetioned in the updates in my A20 manual. The menyion here implies that > the previous manual was wrong. > I agree, this is true 100%. VDD_RTC should be 1.3V. I've tried with 3.3V on one board and fried RTC on it :) So, LDO1SET should be pulled to the ground not Vint. What updates do you mean by the way? Is this a personal list, or is there an official document from someone? > > Cheers, > Steven > Cheers, Ivan -- You received this message because you are subscribed to the Google Groups "linux-sunxi" group. To unsubscribe from this group and stop receiving emails from it, send an email to linux-sunxi+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
