We have a Haswell and 82C226 based design that we have been working on for a while.
With no RTC battery installed, we apply power and we see BIOS output and postcodes changing.
If we install the battery and apply power, nothing happens. The postcode indicator stays
at zero and there is no serial output. The earliest difference in behaviour is that the
SUSWARN# signal (pin AG41) never goes high with the battery installed, but always
goes high with no battery installed. There is a very unhelpful description of this signal
on page 203 of document 486708. The Lava Canyon reference design has this connected
to SUSACK#, which we have also done in our design. Does anyone have any suggestions
about what could be going on here?
Thanks, Paul.