I have made code changes in CCW-Connected Components workbench and downloaded it to the PLC. Is there a way I can directly backup the code from PLC's SD card slot?
Related
I have already posted this question on the raspberry forum but I only got a few answers that didn't solve my problem... I have been waiting for a month so I turn to this forum hoping to be able to find a solution there...
PS : do not hesitate to check my post on RPI forum to see my progress and my research/tests carried out (https://forums.raspberrypi.com/viewtopic.php?t=335338)
So here is my problem :
I have been looking for a while how to write to an external microSD card in SPI mode...
My goal is to write data collected by a sensor an store them on various microSD cards (6) by using CS. But at this point, I'm tring to write data on one card.
I'm using a RPI Zero 2W, a simple microSD card module and an 512GB microSD card (with exFAT filesystem).
I saw that there was a "mmc_spi" driver included in a linux kernel which allows to detect an SD card connected by SPI as if it were a USB key to which we could simply access/read/write (https://ralimtek.com/posts/2016/2016-12-10-raspberry_pi_secondary_sd_card/)
the problem is that this tutorial is not working anymore... In fact, the linux Kernel used in the tuto is an old one compare to the current version and and I had confirmation that the "mmc_spi" driver used to detect the SD card had evolved but the use of this new version is not documented and obviously does not work like the old one...
So my question is : does the mmc_spi driver still allows to detect SD cards and access them and if yes, does it works with the PI zero 2W ?
I have a small IOT app that I've developed on a Raspberry Pi. I'd like to try running the app of a few other Pi's around my apartment. I can make a disk image of the sd card with dd, but, the original disk is 32gb and mostly empty. Is there a way to make a disk image of just the contents of a drive/sd card? This way i can make copies to smaller (cheaper) sd cards. The original SD card was set up with NOOB.
Ordinarily, I'd deploy with something like ansible, but installing all the libraries used took over 8 hours!
I have been using HDDRawCopy to make backup copies of the SD cards for my Raspberry Pi's. It works well and has saved me several times when I have accidently damaged the SD card.
However, several months ago I restored an 8GB SD card image to a 16GB SD card without realizing it. Now, a lot of water has passed under the bridge (changes, new data, etc and several backups) and I want to go back to one of the recent backups.
Yesterday I discovered that a the more recent backup images think they need to be restored to a 16 GB card and fail if I try to restore to an 8GB card, even though I know it would fit.
Is there any way to take the current 16GB SD card and resize it to fit on an 8GB SD card?
I never used that tool. But I used DD in linux, it actually backes up even the empty space..and that is really hard to solve from the .img.
My suggestion is that you flash the backup onto a 16 gb card, flash the vanilla os that u used on a 8gb one, and then copy the files from one to another in a file explorer (only copy the partition that windows can open, the other one/s needs to remain intact)...in raspbian it shall work..
Articles on this topic from 2012 for earlier RPi hardware extolling the virtues of using an external USB flash drive are now dated.
In 2015, using Raspberry Pi 2 hardware, is there still any advantage to moving the root file system and booting from an external USB flash drive instead of just using the default microSD card?
I'm not sure if the raspberry pi bootloader is even capable of booting from USB, but I could be mistaken (there might be a way to set up an SD card to act as an intermediate step in mounting the OS from USB).
Aside from that, I can't imagine you'll notice much of a speed difference between the micro sd and a USB 2 flash drive (as far as I'm aware, the rpi doesn't have usb 3 hardware). Both will have similar life span.
Other considerations: power consumption (I believe SD has an advantage here, especially since a card will have to be used anyway to boot), quality of either device (you can buy really bad SD cards and USB flash drives alike)
I would be interested in seeing some bench marks if you decide to run any tests to see if there's a difference.
My DriveSpeed benchmark measures speed of large and small file writes and reads, plus random writing and reading. RPi 2 results for SD and USB drives are here.
http://www.roylongbottom.org.uk/Raspberry%20Pi%20Benchmarks.htm#anchor21
For booting, you need to establish which performance feature is more important and it is not just large file data transfer speed. Anyway, it mainly depends on the drive hardware performance characteristics. My system SD card can be out performed by SD cards in a USB card reader.
Is there a way to make sure that SD card of Raspberry PI works only with particular device only?
I do not want anyone to use the SD card with any other Raspberry Pi device other than specified.
Is there a way out?
There is no simple way do do this. Of course you can build some trickeries based on Device Informations (fsys and udev) and crypt your disk. But, it is clearly impossible to guarantee system integrity when the storage device is physically reachable: anyone can mount it and some aware/clever guy, using enough time and effort, shall reverse engineering it.
See this guide for Arch linux: https://wiki.archlinux.org/index.php/Disk_Encryption
If you encrypt your filesystem only he have the password can decrypt the sdcard. This prevent unauthorize access for example from the Windows/Linux to the sd card files.
But if you boot from the PC you are in the same problem.
The only thing that comes to mind is to make a script that controls a device that exists only on raspberry is available and if not, automatically encrypt the system.