Re: [Gumstix-users] using ADCIN on 3.0 kernel - no readings for ADC3-6

[Steve S. <sa...@gm...>]

On Thu, Aug 23, 2012 at 10:56 AM, mathineau <mat...@po...> wrote:
> I'm using the last Sakoman's console image, so the patch should be in it,
> isn't it ? I also tried with others images and with the Gumstix connected to
> either Pinto or Tobi.
>
> In every case, I can read the good values on ADC2 and ADC7, but they seems
> to have some crosstalk between ADC3 and ADC4, same thing with ADC5 and ADC6
> as when I put 1.8V on ADC4, I can't read more than 1600 mV on the Gumstix
> and reads 1500 mV on ADC3. If I keep ADC4 connected to 1.8V and connects
> ADC3 to GND, I then read respectively 1.5V and 0.13V.

I just tried an r13 image with all of the adc inputs connected to 1.8V

Every channel reads within a 2 mV range:

root@omap3-multi:~# cat /sys/class/hwmon/hwmon0/device/in2_input
1808
root@omap3-multi:~# cat /sys/class/hwmon/hwmon0/device/in3_input
1810
root@omap3-multi:~# cat /sys/class/hwmon/hwmon0/device/in4_input
1808
root@omap3-multi:~# cat /sys/class/hwmon/hwmon0/device/in5_input
1810
root@omap3-multi:~# cat /sys/class/hwmon/hwmon0/device/in6_input
1810
root@omap3-multi:~# cat /sys/class/hwmon/hwmon0/device/in7_input
1810
root@omap3-multi:~# uname -a
Linux omap3-multi 3.0.0 #1 Tue Jul 24 08:58:09 PDT 2012 armv7l GNU/Linux

I honestly have no clue why it isn't working for you!

Steve