Had real problems upgrading to bone77 which took almost half a day but I 
was eventually successful with the help of bashdb; summary of SPI issues 
after upgrading.

I'm exclusively using spidev now, but I expect the issues will still hold 
for Adafruit_BBIO.SPI.

1) spi1 can still not be used unless device tree for spi0 is first loaded.

2) loading device tree for spi1 and then loading device tree for spi0 shows 
both SLOTS, but spi1 does not work.

3) loading device tree for spi0 and then loading device tree for spi1 shows 
both SLOTS and spi1 now works, but of course the pins used by spi0 are not 
available.

4) errors in /var/log/syslog (i.e. dmesg) occur at the time of loading 
device tree of spi1, but spi1 still works (assuming spi0 was loaded first)

Additional unrelated info; I have been successful at getting edge driven 
interrupt-based callback functions working using Adafruit_BBIO.GPIO by 
trial and error. The documentation on this is sparse to say the least; I 
can't figure out which parameters are acceptable for the functions, and 
what the function actually do; and I can place breakpoints into the 
callback functions using pdb, but they are not triggered even though the 
callback functions are called at the rising edge (as programmed); I haven't 
tried winpdb to get breakpoints in the callback functions but probably will 
sometime in the next couple of weeks.. Summary, this seems to work and may 
be a good approach for GPIO's in python when one does not want to block 
waiting for the edge.

Overall Summary: I2C fine, GPIO fine but sparse documentation, SPI works 
but very flaky and can't use spi1 without wasting pins of spi0

On Monday, September 21, 2015 at 4:29:47 PM UTC-4, RobertCNelson wrote:
>
> On Mon, Sep 21, 2015 at 3:14 PM, Bit Pusher <[email protected] 
> <javascript:>> wrote: 
> > I have been working with programming the BBB's SPI interface in python, 
> and 
> > have become aware of a large number of issues others may be interested 
> in; 
> > if planning on using the SPI interface, I hope this can save others some 
> > time. This is ongoing, so some of these issues may not be real in that 
> they 
> > may be caused by something else I am doing wrong, so please verify for 
> > yourself. If not interested in using the SPI's please just skip. 
> > 
> > Background BBB C: Linux BBB3 3.8.13-bone70 #1 SMP Fri Jan 23 02:15:42 
> UTC 
> > 2015 armv7l GNU/Linux 
> > (note tried upgrading to bone 76, but archive wasn't found - afraid to 
> > upgrade to 3.14 in case everything breaks). 
>
> this ^ issue is now resolved in the repo, bone77 is available to be 
> updated too... (sorry haven't really pushed spi enough to help out 
> with the rest) 
>
> Regards, 
>
> -- 
> Robert Nelson 
> https://rcn-ee.com/ 
>

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