pcf85744
Driver for the pcf8574 8-bit i2c io expander
Usage
To compile this driver into the kernel, place the following lines in your kernel configuration file:
device pcf8574 device gpio device iicbus
Alternatively, to load the driver as a module at boot time, place the following line in loader.conf(5):
pcf8574_load="YES"
Overview
The pcf8574 driver provides gpiobus(4) control over 8 GPIO pins. The pins are quasi-bidirectional. Only low output can be actively driven. High output is equivalent to input.
On an FDT(4) based system the following properties must be set:
- compatible
-
Must be set to "nxp,pcf8574".
- reg
-
The I2C address of
pcf8574.
The DTS part for a pcf8574 device usually looks like:
/ {
...
pcf8574@27 {
compatible = "nxp,pcf8574";
reg = <0x27>;
};
};
Releases
14 releases since FreeBSD 13.1-RELEASE; the text changed 1 time.