Unanswered Questions
701 questions with no upvoted or accepted answers
10
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0
answers
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Cannot Use SPI frequency above 500 kHz
I am running Arch Linux ARM on a Raspberry Pi 2 Model B, and I am attempting to communicate with a TFT display. I am writing a kernel module to interface with the display using SPI, and it works, but ...
- 60.1k
4
votes
0
answers
1k
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FT5406 touchscreen sends events but input does not work
I have a Raspi 3B with the official 7" touchscreen attached. The screen works (showed the under-voltage sign when attaching only the screen controller to a 2.1 A power supply, so I'm connecting ...
- 2,796
3
votes
0
answers
77
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RPI(2) Bare Metal: does GPU support text mode and what is the default video mode?
I'm struggling with trying to find any information about text-mode capability in Raspberry Pi. I'm reading about decompression, 3d, etc. fancy features but I'd like to learn about fundamentals:
Is ...
- 131
3
votes
0
answers
169
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Enabling SPI card reader in device tree on Raspberry Pi
Good evening,
I have MFRC522 card reader. It works well with generic spidev kernel-level driver and high-level python driver. However, as I wanted to learn device trees in linux, I tried to bind ...
- 81
3
votes
0
answers
322
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How to write a Kernel module using SPI properly?
I have no experience writing kernel modules. I build some examples with gpio interrupts and they worked prety well. Now I want to use SPI from my kernel module and I will explain why I need it.
I am ...
3
votes
0
answers
2k
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Error while Starting Raspbian
Enviroment:
Device: Rasberry Pi 2
OS: Raspbian
Last sign of life: 8.March 2021
Problem
Since 8th of march I've got no message of my raspberry pi, so I get them and try to boot with a connected monitor....
- 141
3
votes
2
answers
8k
views
PiHole Not Resolving Local DNS Entries for clients with static IPs
I have a Raspberry Pi 2 running Pi Hole 5.2.2 and Cisco Linksys E2000 router running DD-WRT v24-sp2 (08/12/10) std-usb-ftp
I want to be able to have PiHole resolve a DNS entry such as MyDevice to an ...
CommunityBot
- 1
3
votes
0
answers
533
views
Kivy on Raspberry Pi returning double on_press events
I have an RPi and official touchscreen running Debian Buster and Kivy v1.11.1
using the simple example at https://kivy.org/doc/stable/api-kivy.event.html it is returning double touch events for ...
- 165
3
votes
0
answers
95
views
USB via MAX3421
I am trying to get an additional USB port working by using the MAX3421 chip over SPI on a Raspberry Pi Zero W running raspbian.
I have successfully installed the driver as a kernel module. The chip ...
- 31
3
votes
0
answers
536
views
SPI0 and UART0 interference caused by SPI interrupt
I have a raspberry CM3 running a custom Linux version created by buildroot (kernel: 4.19.44-v7).
The CM3 is configured to be part of a measurement system that is used on a quad-bike (so a lot of ...
- 65
3
votes
2
answers
513
views
Single channel SPI DMA
The documentation on the SPI peripheral says:
Two DMA channels are required, one to read from and one to write to the SPI.
Is this necessarily true? I have a device where I need to write a few ...
CommunityBot
- 1
3
votes
0
answers
673
views
Moonlight (Wifi): Dropped Frames, Multiple Errors, Crash
Casting any media from a PC to the RPi, other than on a Ethernet connection, results in a large number of errors, and an eventual crash. Streams are very responsive, and smooth at 720p at 30fps, but ...
- 31
3
votes
0
answers
1k
views
On-screen keyboard with app integration
I'm aware of matchbox-keyboard, but I'm looking for a more Android or iOS kind of keyboard solution. When selecting a text input, of type alpha or numeric, I would like the appropriate keyboard, text ...
- 183
3
votes
0
answers
11k
views
Raspberry Pi 3 doesn't detect USB touchscreen
I've been trying to get a touchscreen monitor to work with my Raspberry Pi 3. The monitor is 15", externally powered, and is to be connected via HDMI and USB for the touchscreen interface. The HDMI ...
- 31
3
votes
0
answers
725
views
Disable Screensaver of XServer on Raspbian Jessie Lite
I setup a Raspberry Pi 2 with Raspbian Jessie Lite in read only mode. To run a Qt application I installed the packages "xserver-xorg" and "xinit". I am starting the application automatically after ...
- 31