mcp48x1dac(4) - NetBSD Manual Pages

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MCP48X1DAC(4)           NetBSD Kernel Interfaces Manual          MCP48X1DAC(4)


NAME

     mcp48x1dac -- Microchip 48x1 digital to analog converter


SYNOPSIS

     mcp48x1dac* at spi? slave ? flags N


DESCRIPTION

     The mcp48x1dac driver supports the MCP48x1 family of digital to analog
     converters.  The digital values to be converted to analog signal are
     passed through the sysctl(8) node.

     The driver reports the current voltage output on the chip's DAC channel
     through the envsys(4) API.  It calculates these values assuming that
     internal 2.048V reference voltage (Vref) is used.

     The following table shows the supported chips.  The type of the chip can
     be selected with the flags argument in the config file.

           Designation    Resolution    flags
           MCP4801        8 bits        0
           MCP4811        10 bits       1
           MCP4821        12 bits       2


SYSCTL VARIABLES

     The following sysctl(3) variables are provided:

     machdep.mcp48x1dac0.data
             Defines digital data to be converted into analog signal.  This
             value is interpreted literally and sent to the DAC without any
             conversion.  Refer to the chip datasheet for more information.

     machdep.mcp48x1dac0.gain
             When set to 1 it enables 2x output gain on the DAC channel.  The
             default value is 0.


SEE ALSO

     envsys(4), spi(4), sysctl(8)

     MCP4801/4811/4821 8/10/12-Bit Voltage Output Digital-to-Analog Converter
     with Internal VREF and SPI Interface Data Sheet.


HISTORY

     The mcp48x1dac driver first appeared in NetBSD 7.0.


AUTHORS

     The mcp48x1dac driver was written by Radoslaw Kujawa.

     This man page is based on mcp3kadc(4) page by Frank Wille.


BUGS

     There are bugs.

NetBSD 9.4_STABLE               August 23, 2015              NetBSD 9.4_STABLE