config.txt

# Default Nerves RPi config.txt
#
# It's possible to override this file by using a custom fwup.conf
# configuration to pull in a replacement.
#
# Useful links:
# https://www.raspberrypi.org/documentation/configuration/config-txt/README.md
# https://www.raspberrypi.org/documentation/configuration/device-tree.md
# https://github.com/raspberrypi/documentation/blob/master/configuration/device-tree.md
# https://github.com/raspberrypi/firmware/blob/master/boot/overlays/README

kernel=zImage

# Disable the boot rainbow
disable_splash=1

# This, along with the Raspberry Pi "x" firmware is needed for the camera
# to work. The Raspberry Pi "x" firmware is selected via the Buildroot
# configuration. See Target packages->Hardware handling->Firmware.
gpu_mem=192

# Enable I2C, SPI, and audio
dtparam=i2c_arm=on
dtparam=spi=on
dtparam=audio=on

# Comment this in or modify to enable OneWire
# NOTE: check that the overlay that you specify is in the boot partition or
#       this won't work.
#dtoverlay=w1-gpio-pullup,gpiopin=4

# The ramoops overlay works with the pstore driver to preserve crash
# information across reboots in DRAM
dtoverlay=ramoops

# Enable the UART via GPIOs 14 and 15 (ttyAMA0) on the RPi0 W.
# See https://www.raspberrypi.org/documentation/configuration/uart.md.
enable_uart=1
dtoverlay=miniuart-bt
# Set the GPU frequency so that the MiniUART (/dev/ttyS0) can be used for
# Bluetooth. This has a small performance impact. See
# https://www.raspberrypi.org/documentation/computers/config_txt.html#overclocking.
core_freq=250