Firstly thanks for the connector pinouts these are really useful in seeing
how B3 is going together.
So far only two related queries.
I notice that the substitute PINKO connector uses GPIO94 for unsuspend.
On a brief reading of 3.8.1.4 of the PXA270 Developers Manual this does not
seem to be one of the GPIOs that can be programmed as a wakeup, I may well
have missed the point of course...
If this is set to other than GPIO3,1,0 then only "lesser" sleep modes will
be woken up from via this pinko substitute. This may well be a good thing
given the increasing wakeup latency from the successively deeper sleep
modes.
This leads to the second query. If I want to wake up using the backplane I
assume that I can the GPIO lines (e.g. GPIO9,10 as well as 0,1) to do this,
and I assume that these should also be used for external interrupt signals
via the backplane. Is this correct?
a) Is it worth defining which should be used for what?
b) Are these GPIOs free for external use or are they also used on the B3
board? If so can the FPGA/CPLD on B3 be used to make them available by
sharing (note this may well require that they go in and then out of the
FPGA/CPLD to the Samtec connector which they don't currently appear to do).
{I'm inferring, from the connection charts, that for these GPIO's the Samtec
connections are "Tee'd" off the internal signals and not fed via the FPGA
since the this is what the pin counts suggest. (Unlike the Address and Data
bus which clearly go via the FPGA).
Apologies in advance if I've miss read something...
David Bisset
iTechnic Ltd.
(text/plain)