NAME
mcp48x1dac —
Microchip 48x1 digital to analog
converter
SYNOPSIS
mcp48x1dac* at spi? slave ? flags N
DESCRIPTION
Themcp48x1dac 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
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.