Common Device Tree (Jessie) settings
Note. Whilst you can set multiple configurations, some options use the same GPIO pins.
All "dtparam=" configs go into your config.txt (and you must reboot before they will take effect).
I2C - "dtparam=i2c_arm=on"
SPI - "dtparam=spi=on"
I2S - "dtparam=i2s=on"
lirc-rpi - "dtoverlay=lirc-rpi"
The lirc-rpi module parameters are added to the end of the dtoverlay line, like this: "dtoverlay=lirc-rpi,gpio_in_pin=16,gpio_in_pull=high".
w1-gpio -
If you require the external pullup enable pin - "dtoverlay=w1-gpio-pullup,gpiopin=,extpullup="
otherwise - "dtoverlay=w1-gpio,gpiopin="
(where and are GPIO pins, obviously).
If you are using the parasitic power (power over data, 2-wire) mode, add ",pullup=1" (or ",pullup=on")
pps-gpio - "dtoverlay=pps-gpio,gpiopin="
Audio modules - add one of the following:-
dtoverlay=hifiberry-dac
dtoverlay=hifiberry-dacplus
dtoverlay=hifiberry-digi
dtoverlay=hifiberry-amp
dtoverlay=iqaudio-dac
dtoverlay=iqaudio-dacplus
If your card doesn't appear here, you'll need to turn off device tree for now ("device_tree=") and contact the manufacturer for a rebuilt kernal
I2C Real Time Clock - dtoverlay=i2c-rtc,
where is one of: ds1307, ds3231, pcf2127, pcf8523, pcf8563
Use the LED as a 'heartbeat' -