NAME

spi-config - set or query SPI configuration.

SYNOPSIS

spi-config options...

DESCRIPTION

Set or query the configuration of a SPI port.

-d, --device=DEVICE: use the given Linux spidev character device.
-q, --query: print the current configuration.
-m, --mode=[0-3]: set the spi mode (see SPI MODES below).
-l, --lsb={0,1}: set LSB first (1) or MSB first (0).
-b, --bits=[7...]: set the number of bits per word.
-s, --speed=FREQUENCY: set clock frequency (in Hz).
-r, --spirdy={0,1}: set the SPI READY mode flag.
-s, --wait: block, keeping the file descriptor open. See WAIT OPTION below.
-h, --help: display the help screen and exit.
-v, --version: display the version number and exit.

SPI MODES

mode 0: low iddle level, sample on leading edge.
mode 1: low iddle level, sample on trailing edge.
mode 2: high iddle level, sample on leading edge.
mode 3: high iddle level, sample on trailing edge.

WAIT OPTION

On some platforms, the speed is reset to a default value when the file descriptor is closed. To avoid this, one can use the -w option that keeps the file descriptor open. See also last example below.

EXAMPLES

Get help:: $ spi-config -h
Query current configuration:: $ spi-config --device=/dev/spidev0.0 -q
Change clock frequency to 1 MHz:: $ spi-config --device=/dev/spidev0.0 --speed=1000000
Set a configuration and keep the device open:: $ spi-config --wait --speed=1000000 & PID=$!
Close device previously open:: $ kill $PID

AUTHOR

Written by Christophe BLAESS <http://www.blaess.fr/christophe>.

REPORTING BUGS

Github home page: <https://github.com/cpb-/spi-tools.git>

COPYRIGHT

Copyright © 2014 Christophe Blaess.
Licensed under GPLv2 <http://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

August 2014

SPI-tools