SPI-CONFIG

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.