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4 votes

Raspberry Pi is always Read-Only after installing

Since it seems that your /etc/fstab is missing, you may want to fill it in with the necessary information. You'll need to manually mount the root and boot partitions first: sudo mount -o remount,rw ...
RubberStamp's user avatar
  • 1,399
4 votes

How can I use my Raspberry Pi 4 for a write intensive application?

SSDs have wear levelling technology and quote their expected life usually having at least 60Tb of writes before failure. If my calculations are correct and using your 1Mb per minute estimate that ...
Bra1n's user avatar
  • 1,251
3 votes
Accepted

Pi 2: External HDD Randomly goes into Read Only File System Mode

Turns out it was some sort of OS glitch or incompatibility. I ran the following commands overnight and it fixed the problem sudo umount /dev/sda1 # /dev/sda1 is the name of my external drive ...
user2498079's user avatar
3 votes
Accepted

How to persistent write to registers?

Using openssl and public private keys, You could get the pi serial number and encrypt it with a private key, place it on the sd card along with the public key. If you decrypt the file with the public ...
SEWTGIYWTKHNTDS's user avatar
3 votes

Disk access seems slow?

The only check I know of is fsck, and its underlings e2fsck and fsck.vfat. A recent answer here provided a step-by-step procedure for this. There's another utility that may be useful for checking the ...
Seamus's user avatar
  • 22.2k
3 votes
Accepted

Trying to force OpenELEC to keep HDMI on, but fs is readonly

I just installed OpenElec on a Pi 3, and it puts the partition that is normally mounted as /boot on other distributions as /flash. OpenELEC:~ # df | grep p1 /dev/mmcblk0p1 524008 151736 ...
BowlOfRed's user avatar
  • 410
2 votes
Accepted

SPI using SpiDev with LIS2DH sensor, need to send 2 repeated bytes in spi.xfer2 to get data valid back

Thank you @JOAN for clearing things up. need to send 1st byte as command, and then shift out another 8 bits to get my return data. here are two functions that are working for me def readRegister(...
tritium_3's user avatar
  • 121
2 votes
Accepted

Size of serial port read size in c

Assuming we're talking about the hardware UART here, although that is not the default behaviour for the Pi 3 where the PL011 UART is connected to the BT module, while the mini UART is used for Linux ...
Ghanima's user avatar
  • 15.9k
2 votes

Raspbian: mount: / is busy (tried to remount sd card as read only)

If you still can not unmount or remount your device after stopping all services and processes with open files, then there may be a swap file or swap partition keeping your device busy. This will not ...
Simon Gould's user avatar
2 votes
Accepted

Arduino to Pi reads high all the time

Try connecting the wire to another Pin like Pin 11. Then run one of these: gpiozero: from gpiozero import Button from time import sleep button = Button(17) # The 11th Pin is GPIO 17 while True: ...
aklingam's user avatar
  • 974
1 vote

What read protection method is available in RP2040?

There is no read/copy protection. Since the RP2040 has no internal flash, all compiled code is stored in an external QSPI flash and executed 'in-place'. See: https://electronics.stackexchange.com/...
Mattmatic's user avatar
1 vote
Accepted

Is it possible to write to file located in windows directory using Node-Red via ssh?

On your windows computer, use Windows folder sharing to share your destination folder Then mount this shared folder on your raspberry pi Finally, instruct node-red to write to the windows shared ...
Shodan's user avatar
  • 126
1 vote

How to persistent write to registers?

All Pi SOC have a One-Time Programmable (OTP) memory block, indeed this is where the Serial Number resides. See OTP register and bit definitions although as goldilocks pointed out security through ...
Milliways's user avatar
  • 60.3k
1 vote

Raspbian buster read-only system with nmcli issue - No plugin supported adding this connection

Run your rw alias, and then create a test file, e.g. touch ~/testfile. Then reboot and check if the test file is still there. If there is no test file, your rw command is not working as expected, ...
Dmitry Grigoryev's user avatar
1 vote

Unable to get to recovery mode, sd card write protected, vfs error unable to mount root fs on unknown- block(179,2)

Your root filesystem on your SDCard partition #2 (/dev/mmcblk0p2 - device 179,2) is in need of a fsck and the system can't run that automatically. You'll need a new SDCard, a copy of plain Raspbian ...
Dougie's user avatar
  • 5,321
1 vote

Boot from read-only USB media

Standard Linux REQUIRES write access to store temporary files etc. It is possible to make an OS which runs in RAM or which uses RAM for volatile storage. These are commonly used for "Live" ...
Milliways's user avatar
  • 60.3k
1 vote

Raspberry Pi Imager sets the boot partition in read only mode

I guess it is not a problem of the image, or imager, or size of the SD Card. I think it is just a problem of the mount process with your Linux Mint 20 operating system. If the boot partition of the SD ...
Ingo's user avatar
  • 42.2k
1 vote
Accepted

Unable to edit cronjob, /tmp is read-only

First problem: Your /tmp permissions are in order - that's not the problem. First guess is that your filesystem is broken. The solution is to re-flash your SD card (You do have a backup, right?). You ...
Seamus's user avatar
  • 22.2k
1 vote

Unable to edit cronjob, /tmp is read-only

The mode of /tmp is supposed to be 1777. sudo chmod 1777 /tmp The 777 part means anyone can read, write or search the directory. The 1 part means only the owner of each file in the directory is ...
Waxrat's user avatar
  • 556
1 vote

Change the read-only to write

A quick search using the error message in your question was not particularly helpful, but a couple of things come to mind: /tmp is corrupt/mangled your SD card has failed & needs replacement ...
Seamus's user avatar
  • 22.2k
1 vote

How to write 16 bit data to device address using the i2c wiringpi lib

Answer (1) I never use Wiring Pi. So I don't understand your WiringPi problem. (2) I only know how to use smBus to communicate with I2C devices, with or without registers. (3) Referring the ...
tlfong01's user avatar
  • 4,695
1 vote
Accepted

Boot Raspbian from write protected SD; move all data onto external USB drive

A clear and simple way to distinguish "system files" from "user data", the latter including custom installed software (vs. software installed from the distro repository via the package manager) is to ...
goldilocks's user avatar
  • 59.1k
1 vote

Boot Raspbian from write protected SD; move all data onto external USB drive

this little write-lock slider on the edge of every SD card This is just a piece of plastic designed to push a switch in the card reader. This switch is not there in a Raspberry (more precisely, it's ...
Dmitry Grigoryev's user avatar
1 vote

raspberry pi 4 with usb 3 adapter to sata harddrive write slower than usual

Check if you have UAS errors (e.g. sudo dmegs | grep uas): some USB3 storage devices perform better if you disable UAS and use them as good old mass storage. To do so, edit /boot/cmdline.txt and add ...
Dmitry Grigoryev's user avatar
1 vote

Why write a text to file only works when call from terminal?

I'm pretty sure this is a caching problem. The code f = open("test.txt","w") f.write("abc") opens the text file for writing and sends the data abc to it, but this data is not immediately written to ...
sweber's user avatar
  • 516
1 vote

read only Raspbian and microSD partitioning

You can mount your root fs read only, and switch between RO and RW. For switching : I have 2 scripts in /usr/local/bin: /usr/local/bin/rw with inside #! /bin/sh mount / -o rw,remount /usr/local/bin/...
tqhien's user avatar
  • 111
1 vote

Size of serial port read size in c

You can certainly read multiple bytes using read. The comments about FIFO are misleading, even though they are important to ensure high speed troughput, are inaccessable. The kernel drivers almost ...
Milliways's user avatar
  • 60.3k
1 vote

Green Led (ACT) is blinking for mmc0 without SD card activity

I have also asked this question Why is the green LED (ACT) blinking without SD card activity also at the Raspberry Pi Forum and received this answer: by rpdom ยป Wed Feb 22, 2017 8:02 pm From what I ...
Frank Breitling's user avatar

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