MuntsOS Embedded Linux Extra Device Tree Overlays ================================================= Here are some collected device tree overlays for Raspberry Pi boards that have been written from scratch or customized from the kernel source distribution for MuntsOS. For I^2^ devices, the easiest way to determine the correct slave address is to run **`i2cdetect -y 1`** before and after attaching the device and see what changes. Then you can add the proper **`dtoverlay`** command to **`/boot/config.txt`** ### AD5593R Analog/Digital I/O Expander dtoverlay=AD5593R dtparam=mode0=1 dtparam=mode1=1 dtparam=mode2=1 dtparam=mode3=1 dtparam=mode4=1 dtparam=mode5=1 dtparam=mode6=1 dtparam=mode7=1 dtparam=offstate0=0 dtparam=offstate1=0 dtparam=offstate2=0 dtparam=offstate3=0 dtparam=offstate4=0 dtparam=offstate5=0 dtparam=offstate6=0 dtparam=offstate7=0 ----------------------------------- ----------------------------------- **Mode Values** **Off State Values** 0 Unused\ 0 Pulldown resistor 1 ADC\ 1 Output low (sinking) 2 DAC\ 2 Output high (sourcing) 3 ADC and DAC\ 3 Tri-State (high impedance) 8 GPIO ----------------------------------- ----------------------------------- ### ADS1015 Analog to Digital Converter dtoverlay=ADS1015 dtparam=addr=0xNN dtparam=cha_enable dtparam=chb_enable dtparam=chc_enable dtparam=chd_enable dtparam=cha_cfg=4 dtparam=chb_cfg=5 dtparam=chc_cfg=6 dtparam=chd_cfg=7 dtparam=cha_gain=0 dtparam=chb_gain=0 dtparam=chc_gain=0 dtparam=chd_gain=0 The I^2^C slave address may be 0x48 or 0x49. ### ENC28J60 Ethernet Adapter dtoverlay=ENC28J60 dtparam=cs=N dtparam=irq=N The value for the SPI slave select parameter **`cs`** is 0 for **`spidev0.0`** or 1 for **`spidev0.1`**. Default is 0.\ The value for GPIO interrupt signal parameter **`irq`** must be a GPIO number. Default is 25. The default values are correct for the [GeeekPi EN28J60 HAT](https://www.seeedstudio.com/ENC28J60-OVERLAYS-HAT-for-Raspberry-pi-p-3045.html) so both **`dtparam`** lines may be omitted. Other ENC28J60 boards such as the [Mikroelektronika ETH Click](https://www.mikroe.com/eth-click) will likely require **`cs`** or **`irq`** or both. ### MCP23017 GPIO Expander dtoverlay=MCP23017 dtparam=addr=0xNN dtparam=gpiopin=N The I^2^C slave address may be 0x20 to 0x27. ### PCA8574 GPIO Expander dtoverlay=PCA8574 dtparam=addr=0xNN The I^2^C slave address may be 0x20 to 0x27 (PCA8574, PCF8574) or 0x38 to 0x3F (PCA8574A, PCF8574A). ### PCA9685 PWM Expander dtoverlay=PCA9685 dtparam=addr=0xNN Possible I^2^C slave addresses range from 0x40 to 0x7F, though some of these will conflict with other devices and reserved addresses. 0x40 and 0x70 are common. This overlay does not support GPIO mode. ### W5500 Ethernet Adapter dtoverlay=W5500 dtparam=cs=N dtparam=irq=N The value for the SPI slave select parameter **`cs`** is 0 for **`spidev0.0`** or 1 for **`spidev0.1`**. Default is 0.\ The value for GPIO interrupt signal parameter **`irq`** must be a GPIO number. Default is 25. ------------------------------------------------------------------------ Questions or comments to Philip Munts