spi-config1
Set or query spi configuration.
Usage
spi-config options ...
Overview
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
History
- Debian 13 (Trixie) to Debian 11 (Bullseye): the text shown here
- Debian 10 (Buster)
--spirdy since Debian 11 (Bullseye);
--wait since Debian 11 (Bullseye);
-r since Debian 11 (Bullseye).