17
votes
What does "dtoverlay=dwc2" REALLY do?
The answer to your question title has been hard to word better than gregeric explained:
dwc_otg is the driver that has been heavily patched to squeeze most performance & function in host mode on ...
- 2,884
10
votes
Accepted
Enabling ARMv8 on Raspberry Pi 3 B
I think others here have done a good job answering:
Is it even worth switching from ARMv7 to ARMv8
Various software cited to require ARMv8 includes CockroachDB, MongoDB (if accessing >2 GB), the ...
- 2,884
8
votes
Enabling ARMv8 on Raspberry Pi 3 B
Is it even worth switching from ARMv7 to ARMv8?
Not unless you are running a kernel and OS userland compiled for ARMv8; there are at least a few such things for the Pi 3 around, including Fedora. ...
- 58.3k
7
votes
config.txt : Hostname
It is not possible to set the device hostname through config.txt. A full list of commands can be found on the Raspberry Pi Foundation's website.
An Alternative:
You mention that you're creating a ...
- 11.9k
6
votes
over_voltage possible values
The permitted over voltage values are given in
https://www.raspberrypi.org/documentation/configuration/config-txt/README.md
CPU/GPU core voltage adjustment. [-16,8] equates to [0.8V,1.4V] with
0....
- 70.4k
6
votes
Does hdmi_cvt need the '=' in config.txt?
I've just tested this on my Pi3 with 5 inch touchscreen - both work - with and without the '='.
hdmi_group=2
hdmi_mode=87
hdmi_cvt=800 480 60 6 0 0 0
Worked
hdmi_group=2
hdmi_mode=87
hdmi_cvt 800 ...
- 6,727
6
votes
Raspberry Pi 4 B GPIO boot and shutdown button(s)
I see two separate questions re use and configuration of "power buttons" to halt and boot an RPi 4:
Question 1:
Is the shutdown initiated with connecting the GPIO3 pin and the GND pin ...
- 20.7k
6
votes
Accepted
is dtoverlay a general linux concept or RPi specific?
dtoverlay and /boot/config.txt is a very nice method to quickly tell the kernel that you've got new device tree information.
Worth making explicit that config.txt is not accessed by the kernel at all,...
- 58.3k
6
votes
is dtoverlay a general linux concept or RPi specific?
Device Tree is a data structure for describing hardware.
Rather than hard coding every detail of a device into an operating system, many aspects of the hardware can be described in a data structure ...
- 58.2k
5
votes
Accepted
How to edit config.txt
/boot mounted as read-only
Issue a
mount | grep /boot
if the the output is
/dev/mmcblk0p1 on /boot type vfat (ro,relatime, ... ,errors=remount-ro)
it is mounted read-only (see the ro). You can ...
- 593
5
votes
Accepted
Restoring OTP bit after using MSD boot feature
I understand this is an old question, but happens that I knew how this is working trying to fix a similar problem (more on this later on).
Yes you can boot again from the sdcard, even with the (...
- 174
5
votes
Unable to set GPU memory split on Raspberry Pi Zero W
Thanks to the forums over on raspberrypi.org I was able to find out the answer to this, so I am sharing it here for future reference...
ANSWER: The 128M of GPU RAM is still being reserved because I ...
- 993
4
votes
Accepted
Why is the L2 cache disabled by default on Raspbian Jessie?
On the Pi1 there was a L2 cache which was primerally intended for use by the VPU but could also optionally be used by the arm core. IIRC in the intial firmware the arm didn't use this cache but with ...
- 6,032
4
votes
Accepted
`arm_freq` in config.txt on Raspberry Pi 3 model B
The Raspberry Pi 3 Model B starts at 1.2Ghz regardless of what /boot/config.txt says. Here are the results of my clock speed files on my Pi 3 with config.txt not edited from a fresh card:
sudo cat /...
- 6,355
4
votes
How to set the video resolution over composite?
I read at https://discourse.osmc.tv/t/composite-sd-resolution-of-osmc-skin-video-output/5445/3) that
Composite is fixed resolution (720x480@60i for NTSC, 720x576@50i for PAL).
So you cannot change ...
- 967
4
votes
Raspberry Pi 4 B GPIO boot and shutdown button(s)
The operation is explained in /boot/overlays/README
It is quite safe, I have it on all my Pi in case I need to shutdown a headless Pi (or one without keyboard attached), although my Pi are rarely ...
- 58.2k
3
votes
Accepted
"chmod u+w config.txt" results in "Operation not permitted."
You probably need to use sudo:
sudo chmod a+w config.txt
Explanation:
You don't say much about the file (who owns it?) or which user you're running the command as, but I guess you're probably logged ...
- 1,293
3
votes
config.txt : Hostname
Okay, from your comments on the other answer, it looks like you want to change the hostname of Raspberry Pi image without actually booting it. This should be trivial.
We want to modify the /etc/...
3
votes
Accepted
Raspberry Pi 2: HDMI resolution to 1280x1024 60 hz
For me to set raspberry_pi raspbian(jessie) video resolution as 1280x1024, from 655x500(some very large and disturbing display resolution) I have made following changes in my /boot/config.txt file.
...
- 146
3
votes
Accepted
Raspberry Pi B+ Overclocking
Setting the governor to "performance" should mean the processor runs at the maximum frequency set in config.txt, or the default if there isn't one. Note that this is generally pointless except in ...
- 58.3k
3
votes
Enabling ARMv8 on Raspberry Pi 3 B
As of today, it seems Fedora and Archlinux are well supported.
If you go the Arch way, this will help you build the image (for me on linux / rpi3 it was make linux) and this will help you start wifi....
3
votes
Accepted
Setting up multiple I2C buses using dtoverlay
Looks like you're using the physical pin numbers.
All RPF documentation, settings and software (such as dtoverlay, gpiozero, etc) work with the BCM numbers.
You can find these at pinout and elsewhere....
- 3,496
3
votes
Accepted
How do I regain access to either the filesystem or terminal on a raspberry pi that has all networking services disabled and no terminal?
Your SD card (or whatever media you boot from) has two partitions - one is ext4 filesystem (/); the other is FAT32 filesystem (/boot). You may remove the SD card, then mount and edit anything in /boot ...
- 20.7k
3
votes
How do I regain access to either the filesystem or terminal on a raspberry pi that has all networking services disabled and no terminal?
Try adding rw init=/bin/bash to the cmdline.txt: that should unconditionally boot your system into a root terminal, which allows you to edit the configuration files you have messed up (re-enabling the ...
- 27.6k
2
votes
How do I increase the terminal font size?
7 years later, I was having the same issue, and the solution that worked for me was "Method 2" from https://www.raspberrypi-spy.co.uk/2014/04/how-to-change-the-command-line-font-size/.
In short, I ...
2
votes
How do I increase the terminal font size?
Here's the simplest solution: When you log in to Linux (or Unix) a file named .profile is executed by the shell. I recently got a 7" LCD, 1024x600 monitor. For the last 2 years I've communicated with ...
- 21
2
votes
Why won't my Raspberry Pi overclock?
for me it was the scaling governor which prevented the overclocking.
just read the correct answer on this question here: How to change the default governor?
now my raspberry runs on 1150MHz
- 173
2
votes
Accepted
How to Create shortcut that appends text to /boot/config.txt
You should use one of kdesu, kdesudo or gtksudo (depending on your desktop environment) to run the script as root. It will give you a gui prompt for your password rather than just sudo which wants an ...
- 761
2
votes
Kernel log ONLY on serial console (UART)
To get the requested logging it's not enough configuring only the kernel, config.txt and cmdline.txt. You need to disable tty1 login in "init" config as well. My project Nard SDK does pretty much ...
- 888
2
votes
Why is the L2 cache disabled by default on Raspbian Jessie?
I get the same thing (disable_l2cache=1) without overclocking on a Pi 2 running a stock 4.1.9-v7+ kernel and the latest firmware update. The distro is Fedora 21, but I do not think the distro will ...
- 58.3k
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