Have you had any luck getting the spi0 clock working on the BBB (rev A6) 
using Ubuntu (3.8.13-bone30) ? I've done all the following
1) Added "capemgr.enable_partno=BB-SPIDEV0" to uEnv.txt in boot/uboot . 
This is the right uEnv.txt file as its in the FAT boot portion.
2) checking with "cat /sys/devices/bone_capemgr.9/slots"  I see the SPIDEV 
override
3) checking "ls -al /dev/spi*" I get the expected "/dev/spidev1.0 and 
/dev/spidev1.0" files
4) I added Adafruit_BB library and the CS pin (P9_17) can be toggled from 
here
5) Shorting pins 21 and 18 I can see data transfer so internally the spi 
clock works as expected.

However connected SPI_CLK(P9_22) to a logic analyzer I see no clock signal! 
I am certain the logic analyzer is ok since with hdmi enabled I can see 
clock signals on pins 25 and 31. I don't know why I am not getting a clock 
signal for SPI0. I just get the clock 'low'. The same thing happens when I 
disable hdmi and enable spidev1 instead; I get no clock signal on SPI1 
clock  (pin 31). 

Any suggestions on what I may be missing? 

Le mardi 1 octobre 2013 10:55:57 UTC-5, [email protected] a écrit :
>
> Rafael, Would you mind posting you DTS file??? I have been trying to make 
> the SPI clocl work, but I haven't had any luck!
>
> Thank you, 
>
> Laura
>
> El lunes, 16 de septiembre de 2013 07:28:18 UTC-4, Rafael Fiebig-Bindner 
> escribió:
>>
>> Just for clearence: Deactivate Pullup/-down is only needed at clock. 
>> Am Montag, 16. September 2013 11:22:43 UTC+2 schrieb Andrew Wagner:
>>
>>> Hi Arlen, 
>>>
>>> The coverage for setup up a device overlay tree here is pretty good: 
>>>
>>>
>>> http://learn.adafruit.com/introduction-to-the-beaglebone-black-device-tree/overview
>>>  
>>>
>>> With that and glancing at some other samples, we were able to get 
>>> writing to work.  We did not get reading working in time for our 
>>> deadline, and resorted to bitbanging from userspace code.   I have not 
>>> had a chance to try Rafael's advice (clock as input, deactivate pull 
>>> up / pull down). 
>>>
>>> Cheers, 
>>> Andrew 
>>>
>>

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