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LED Matrix Scrolling text with Arduino using a 74HC595

The extension to the previous letter guessing game, I found a font library from a post in Instructables, and this leading me to create a scrolling text message to the single LED Matrix. This can be combined to make bigger display.

Nostalgic memory remembering what one of my Uni friend’s project back 20 years ago using shift registers and pascal programming, we had come a long way to simplify the circuitry and reduce the complexity of both hardware and software.

Please contact me if you would like the source code or the copy of the fonts library.


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Emergency recovery shell in berryboot

Every now and again you would experiment with things in raspberry pi, in this instance I am playing around with the wall display called Dakboard, so I modify the config.txt file /boot, and because I had berryboot, it freak out and drops to “emergency recovery shell”.

In order to restore the config.txt file do the following in the command line, because berry boot doesn’t haveĀ  /boot partition by design we will have to create one:

cd /
mkdir boot
mount /dev/mmcblk0p1 /boot
vi /boot/config.txt

At this point you can edit the config back to the original or restore it from the backup (what? you didn’t make a back up?)

Once you restore it to the original, you will have to unmount the boot partition back using

umount /boot

Then reboot by using the Ctrl + Alt + Del key or power cycle the pi. This should then boot back to berryboot gui for you to perform any changes.