Object : example of PCF8574 button proc driver
Test HW: Linkit 7688
Test SW: openwrit 3.18.109
Usage:
copy hello_btn to openwrt/package/kernel
make menuconfig
select
Kernel modules
Other modules
[*]kmod-hello_btn
make package/hello_eeprom/compile V=s
opkg install ipk to Linkit 7688
cat /proc/HELLO_BTN
Note:
The analog button seems simple.
But, after 1~3 years, the button maybe be damped and there is some resistance.
One day, you want to press button to cancle launching missle.
But,bad button launches the missile XD