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TI_ADC(4)		 arm Kernel Interfaces Manual		     TI_ADC(4)

NAME
       ti_adc -- TI AM3XXX analog to digital converter driver

SYNOPSIS
       device ti_adc

DESCRIPTION
       The  ti_adc driver provides access to the AIN (analog inputs) on	am3xxx
       SoCs.

       It provides raw readings	of the converted values	for  each  analog  in-
       puts.

       The access to ti_adc data is made via the sysctl(8) interface:

       dev.ti_adc.0.%desc: TI ADC controller
       dev.ti_adc.0.%driver: ti_adc
       dev.ti_adc.0.%pnpinfo: name=adc@44E0D000	compat=ti,adc
       dev.ti_adc.0.%parent: simplebus0
       dev.ti_adc.0.clockdiv: 2400
       dev.ti_adc.0.ain.0.enable: 0
       dev.ti_adc.0.ain.0.open_delay: 0
       dev.ti_adc.0.ain.0.samples_avg: 0
       dev.ti_adc.0.ain.0.input: 0
       dev.ti_adc.0.ain.1.enable: 0
       dev.ti_adc.0.ain.1.open_delay: 0
       dev.ti_adc.0.ain.1.samples_avg: 0
       dev.ti_adc.0.ain.1.input: 0
       dev.ti_adc.0.ain.2.enable: 0
       dev.ti_adc.0.ain.2.open_delay: 0
       dev.ti_adc.0.ain.2.samples_avg: 0
       dev.ti_adc.0.ain.2.input: 0
       dev.ti_adc.0.ain.3.enable: 0
       dev.ti_adc.0.ain.3.open_delay: 0
       dev.ti_adc.0.ain.3.samples_avg: 0
       dev.ti_adc.0.ain.3.input: 0
       dev.ti_adc.0.ain.4.enable: 0
       dev.ti_adc.0.ain.4.open_delay: 0
       dev.ti_adc.0.ain.4.samples_avg: 0
       dev.ti_adc.0.ain.4.input: 0
       dev.ti_adc.0.ain.5.enable: 0
       dev.ti_adc.0.ain.5.open_delay: 0
       dev.ti_adc.0.ain.5.samples_avg: 0
       dev.ti_adc.0.ain.5.input: 0
       dev.ti_adc.0.ain.6.enable: 1
       dev.ti_adc.0.ain.6.open_delay: 0
       dev.ti_adc.0.ain.6.samples_avg: 4
       dev.ti_adc.0.ain.6.input: 2308
       dev.ti_adc.0.ain.7.enable: 1
       dev.ti_adc.0.ain.7.open_delay: 0
       dev.ti_adc.0.ain.7.samples_avg: 0
       dev.ti_adc.0.ain.7.input: 3812

       On  Beaglebone-black  the  analog input 7 is connected to the 3V3B rail
       through a voltage divisor (2:1).	 The 3V3B voltage rail comes from  the
       TL5209 LDO regulator which is limited to	500mA maximum.

       Global settings:

       dev.ti_adc.0.clockdiv  Sets the ADC clock prescaler.  The minimum value
			      is  10  and the maximum is 65535.	 The ADC clock
			      is based on CLK_M_OSC (24Mhz) / clockdiv.	  This
			      gives a maximum of ~2.4Mhz for the ADC clock and
			      ~10Khz  for  the	default	 setting  (clockdiv  =
			      2400).

       Settings	per input:

       dev.ti_adc.0.ain.%d.enable	Enable the conversion for  the	input.
					Each  input should be individually en-
					abled before it	can be used.  When all
					the inputs are disabled,  the  ADC  is
					turned off.

       dev.ti_adc.0.ain.%d.open_delay	Sets the number	of ADC clock cycles to
					wait after applying the	input configu-
					ration	and  before start the ADC con-
					version.

       dev.ti_adc.0.ain.%d.samples_avg	Sets the  number  of  samples  average
					used on	each input, it can be set to 0
					(no samples average), 2, 4, 8, or 16.

       dev.ti_adc.0.ain.%d.input	Is  the	 converted  raw	 value	of the
					voltage	applied	on the	analog	input.
					It  is	made  of  a  12	bit value (0 ~
					4095).

SEE ALSO
       sysctl(8)

HISTORY
       The ti_adc driver first appeared	in FreeBSD 10.1.

AUTHORS
       The driver and this manual page was written  by	Luiz  Otavio  O	 Souza
       <loos@FreeBSD.org>.

FreeBSD	15.0			 June 1, 2014			     TI_ADC(4)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=ti_adc&sektion=4&manpath=FreeBSD+15.0-RELEASE+and+Ports>

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