The device-tree tag has no usage guidance.
1
vote
1answer
41 views
Emulate Raspberry Pi zero W with Qemu failed due to missing dtb
I am trying to emulate a Raspberry Pi zero W with Qemu based on an image I used on a real Raspberry Pi zero W.
The command I am using is:
sudo qemu-system-arm \ ...
0
votes
0answers
50 views
Connecting RAW NAND through GPIO
I'm trying to define a device tree for connecting an external raw NAND using GPIO on RPI3.
I found that there are available drivers, and I found an example in the sources' "Documentation" directory
...
1
vote
1answer
31 views
How and from where is the ENC28J60 driver loaded?
I have a raspberry CM3 setup where I added an external eNet port so that I have internet connectivity. It is very similar to the break-out board setup such as this one which is also based on the ...
1
vote
2answers
351 views
Rpi3 is the hardware watchdog enabled by default
I have RaspberryPI's 3 (running both Jessie and Stretch) and tested on both
In order to enable the watchdog timer, In many posts I saw that add in the /boot/config.txt a line with:
dtparam=watchdog=...
2
votes
1answer
42 views
Change Device Tree to pullup pin at boot
I trie to add a LTC2954 to the raspberry pi zero w. I designed and produced a prototype pcb with an lipo management system for load and loadsharing. My problem is, that the KILL Pin of the LTC2954 has ...
0
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0answers
40 views
Difference between sound and audio nodes in RPi 3 device tree?
I looked a bit into the device tree of Raspbian 9 on Raspberry Pi 3, using:
dtc -I fs /proc/device-tree > myrpi-dev-tree.txt 2>&1
I've noticed there is a node called audio:
audio {
...
2
votes
0answers
65 views
Raspberry Pi remap DPI pins [closed]
I'm trying to hook up my Raspberry Pi a to custom display hat via the parallel display interface (GPIO Pins, not ribbon cable). The problem I'm facing is that the DPI pins are rather awkwardly placed ...
0
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0answers
50 views
DTS Overlays Makefile
I'm going to add a new entry in the Makefile.
The suggested syntax for that entry is
dtbo-$(RPI_DT_OVERLAYS) +=
.
Looking at the list already loaded in Makefile I see a different syntax:
dtbo-$(...
1
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0answers
40 views
Access more than two (2) slaves on spi0
Supposedly, there is a new driver that supports arbitrary GPIOs for SPI0 channel select, that is configurable via the device tree.
Everything I try only half works. The hard works. If I toggle the ...
1
vote
0answers
155 views
Accessing 3+ SD/MMC /dev/mmcblk devices
I've successfully followed some instructions for access 2 SD cards via SPI on a Raspberry Pi 3: https://ralimtek.com/Raspberry_Pi_Secondary_SD_Card/
How do I configure it to access more than 2 SD ...
1
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0answers
60 views
In simultaneous use of SPI0 and DPI Mode 3 interfaces, can SPI0 CS0 be moved to a pin other than 8?
I am attempting to design a device using a Pi Zero which needs to connect to both an ENC18J60 SPI ethernet controller, and a VGA monitor via Mode 3 DPI and the Mincepi Pi Zero pi2vga schematic. While ...
1
vote
1answer
484 views
dtoverlay=gpio-poweroff not working on raspberry pi 3 B
Problem:
I have a Raspi 3B rev: a02082 (Q1 2016 3 Model B 1.2 1 GB (Mfg by Sony)) running raspbian jessie kernel 4.9.35-v7
I want to signal to a power management circuit that filesystems ...
0
votes
0answers
158 views
SPI doesn't work because of device tree
I have the same problem as this person:
SPI enabled in device tree, but I can't use it
I tried commenting in the original thread but the community rules don't allow me to comment because I don't ...
1
vote
1answer
545 views
How do i use DeviceTree to init GPIO to a set value?
Hello i've got a board connected to my raspberry pi 3 and according to the pin set on boot of the raspberry this shield reboot which is problematic. I need to be able to reset the board and control ...
3
votes
1answer
41 views
DeviceTree magic strings
I recently stumbled over the MagPi Essentials Camera. In chapter 7 "Flash photography using an LED" (p.41+), they show how to configure pin BCM17 to act as a flash for the official Raspberry Pi Camera....
2
votes
0answers
237 views
device tree and led blink
I am trying to create one led driver via device tree in Rpi 3
I had created the dtsi file
/dts-v1/;
/plugin/;
/ {
compatible = "brcm,bcm2837";
fragment@0 {
target = <&...
0
votes
0answers
14 views
Making Overlays Function Before Login
I am using a custom overlay such that the pi will halt when gpio-5 is shorted to gpio-6. Then a second overlay (gpio-poweroff) lets my UPS know it is safe to remove power. Config.txt calls the ...
4
votes
1answer
2k views
SPI enabled in device tree, but I can't use it
I am trying to use SPI interface on Raspberry Pi 1 B (OS: Raspbian July 2017, kerenl 4.9.5). To do this, I am using wiringPi. I confirmed that wiringPi works via gpio readall
To load SPI:
gpio load ...
0
votes
2answers
341 views
How to use advanced GPIO functions via sysfs?
The GPIO ports can be accessed using sysfs interface located in /sys/class/gpio. However, I failed to found more detailed documentation, most of which only describes plain read/write operation.
What ...
3
votes
1answer
634 views
How to build my very own device tree (and if I need to)
Let me preface this by saying I don't know much about device trees. I do know a bit about ATAGs, since I'm working with this operating system that currently only uses ATAGs.
I'm modifying the ...
0
votes
1answer
323 views
apds 9960 on raspberry pi zero
I would like to use the apds9960 (light/gesture sensor) on rp0 - utilizing the kernel iio driver, which is already available, but there is no dt overlay yet. I guess I need to:
write the dts file
...
0
votes
1answer
1k views
Compile a dts file (dt overlay)
Hello folks maybe I have misunderstood something but I am not sure how to compile my dt overlay file with the etc command (!) I already know that I have to use the @ parameter .
The effect of ...
3
votes
1answer
1k views
How to use BMP280 SPI Kernel Module
I got a adafruit BME280 sensor board and I wired it to the raspberry pi zero via spi. According to the datasheet I can read sensor data from the device via the userspace spi interface. Everything ...
0
votes
1answer
550 views
Disable pull-up resistor on pps-gpio pin
I am using the pps-gpio dtoverlay. My /boot/config.txt has these lines:
# Expect the GPS 1PPS pin to be connected to GPIO3
dtoverlay=pps-gpio,gpiopin=3
Problem is, that the GPS Module (SkyTraq Venus)...
2
votes
1answer
3k views
Missing configuration options on raspi-config screen??? No SPI or Device Tree
Downloaded NOOBS onto my SD card and got my RPi3 up and running.
I'm trying to enable Device Tree and SPI via the advanced options bit on the raspi-config blue screen (so i can install my 3.5inch ...
0
votes
1answer
557 views
How to detect a device tree overlay at run time?
What is the best way to check at run time if a device tree overlay is loaded?
I've found info about checking individual GPIO pin status, and info about how to load the overlay (via config.txt), but I'...
0
votes
2answers
3k views
how to enable spi1? / pi 3 and two rc522 RFID readers
Is it possible to connect two RC522 readers with one RaspberryPi 3?
As far as I know I should just choose different CS pins for them (Add more than 2 SPI slaves).
I have following connections:
1st ...
1
vote
2answers
333 views
Raspberry pi HAT device-tree
I'm currently developping a Raspberry pi HAT. The Raspberry pi HAT must contain a EEPROM with several information in it. This information will be read at boot time in order to configure the Raspberry ...
0
votes
1answer
230 views
device tree and spi controller file
why is the file spi_bcm2708.c is not present inside the path linux/drivers/spi and while inside the boot partition of pi the bcm2708-rpi-version.dts file is only present.how come kernal use the ...
2
votes
1answer
624 views
i2c on a rpi-basic-image created with yocto
I'm attempting to get the i2c bus to work from a raspberry pi image created from yocto. I have looked at other peoples solutions but they are all o do with raspbian or some other flavour of os.
My /...
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0answers
128 views
Restoring Wi-Fi while keeping device tree disabled
Although it's advised to keep it enabled, it was the only way for me to get an NFC board working but just like this forum thread states, disabling the device tree makes the wlan interface disappear.
...
1
vote
1answer
1k views
unable to install 1-wire temperature sensor
I am trying to figure out why I cannot get temperature sensors working connected to my RPi2. I have followed almost every possible guide on the internets without luck and the answers* provided here ...
5
votes
5answers
2k views
DS18B20 w1-gpio Device Tree gpiopin NOT = 4
I have a HAT which blocks GPIO4 so I cannot use the default pin for the temperature sensor, but I just cannot get it to work on another pin!
I just get lots of 00- instead of 28- in /sys/bus/w1/...
1
vote
0answers
325 views
Setup gpio 23 as shutdown & startup
Followed this tutorial & have included my device tree config below. I've configured my pull up resistor for my button to function properly once my app is running, but I'm curious; is there a way ...
2
votes
1answer
3k views
How to use i2c_gpio with Raspberry Pi?
I would like to use the i2c_gpio software i2c kernel module because the broadcom hardware i2c does not support I2C_M_NOSTART. How do I do this?
I think that in order to do it I need to take the ...
