I've not really had a lot of trouble getting my One Wire temperature sensor 
to function.  But there have been lots of stumbles and I'm still confused 
in a lot of places.  Let's start with what I'm running on a BBB RevB with 
the OS on a 16GB MicroSD card.  
uname -a for all shows:
Linux beaglebone 4.1.4-ti-r8 #1 SMP PREEMPT Thu Aug 6 21:01:16 UTC 2015 
armv7l GNU/Linux

I've configured w1.dts and used dtc to create the w1-00A0.dto which is in 
Now here is where it starts to get complicated mostly because of the OS 
changes I believe.

First of all I've got my DS1822 (1 wire with +/-2C resolution with 22- 
code) wired through a connector onto the SparkFun prototype cape.  The 
EEROM on the cape is not yet programmed with anything so it's not in the 
list.  A 
cat $SLOTS 
 0: PF----  -1
 1: PF----  -1
 2: PF----  -1
 3: PF----  -1
 5: P-O-L-   0 Override Board Name,00A0,Override Manuf,w1

Notice that neither the HDMI nor the eMMC show up like they do on all the 
various examples on the web.  I'm using the MicroSD card since the BBB has 
only 2GB.  I'm operating headless with Ethernet and puTTY s there's nothing 
on the USB nor HDMI connector.  Perhaps because nothing's using them?
This is an example from 

$ cat /sys/devices/bone_capemgr.*/slots
0: 54:PF--- 
1: 55:PF--- 
2: 56:PF--- 
3: 57:PF--- 
4: ff:P-O-L Bone-LT-eMMC-2G,00A0,Texas Instrument,BB-BONE-EMMC-2G
5: ff:P-O-L Bone-Black-HDMI,00A0,Texas Instrument,BB-BONELT-HDMI

And to get the One wire W1 virtual cape installed I've copied 
 sudo sh -c "echo w1 > /sys/devices/platform/bone_capemgr/slots"

Again, this is where it's interesting.  After a restart this Debian Jesse 
image installs the 

cat $SLOTS
 0: PF----  -1
 1: PF----  -1
 2: PF----  -1
 3: PF----  -1
 4: P-O-L-   0 Override Board Name,00A0,Override Manuf,cape-universaln

To load the virtual One Wire I first have to remove the cape-universaln 
because it's already claimed the P8-11 pin I'm using for the DS1822.  
That's pretty easy once we know the virtual cape #
 sudo sh -c "echo '-4' > /sys/devices/platform/bone_capemgr/slots"

One other thing that's different from the various forum examples is the 
location of the slots file.  

cat /sys/devices/bone_capemgr.*/slots

The newer Debian image now adds 'platform' after devices and has trashed 
the .x after bone_capemgr. No more .7 or .9

And thenthe web documentation appears to get rather sparse.
1. I can't find where from the cape-universal.dtbo is loaded and which 
script puts it into the slots file.
2. There are several different copies of the cape-universaln.dts so which 
one is the correct one?
3. Is there a way to disable the pin used by the W1.dts so the SparkFun 
EEROM can be programmed with the information in the w1.dts file?  Without 
recompiling the cape-univesal.dts file with the reference to the W1 pin 

Here's where my system has the various .dts files.  Which one is loaded?  
beaglebone- or bb.org-overlays?  

 sudo find -name cape-universal*


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