MCP3KADC(4)

NAME
mcp3kadc - Microchip 3x0x SAR analog to digital converter

SYNOPSIS
mcp3kadc* at spi? slave ? flags N

DESCRIPTION
The mcp3kadc driver reports the current voltage on the chip's ADC channels through the envsys(4) API. The driver calculates these values according to the currently selected reference voltage (Vref). It can be changed through the sysctl(8) node hw.mcp3kadc0.vref.

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 | Input Channels | flags
MCP3001 | 10 bits | 1 | 0
MCP3002 | 10 bits | 2 | 1
MCP3004 | 10 bits | 4 | 2
MCP3008 | 10 bits | 8 | 3
MCP3201 | 12 bits | 1 | 4
MCP3202 | 12 bits | 2 | 5
MCP3204 | 12 bits | 4 | 6
MCP3208 | 12 bits | 8 | 7
MCP3301 | 13 bits | 1 | 8
MCP3302 | 13 bits | 4 | 9
MCP3304 | 13 bits | 8 | 10

SYSCTL VARIABLES
The following sysctl(3) variables are provided:

hw.mcp3kadc0.vref
    Defines the reference voltage on the chip's Vref pin in millivolts (mV). It defaults to the ADC's maximum output value + 1 in millivolts (e.g., 4096 for a 12-bit ADC).

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

HISTORY
The mcp3kadc driver first appeared in NetBSD 8.0.

AUTHORS
The mcp3kadc driver was written by Frank Wille.