Hi, I'm having a similar issue after modifying the config.txt file
I only recieved my 512 MB Pi today so please forgive me if I seem a bit clueless...
I installed the latest version of Raspbian Wheezy (25th May 2013) and managed to get that working fine, no problems at all. I then decided that I wanted to flip the screen around so I edited the config.txt file using nano (sudo nano /boot/config.txt) by adding the following line and saving it:
I then rebooted the Pi using the appropriate command (sudo shutdown -r now). However the Pi does not appear to reboot properly, there is nothing displayed on the screen at allthough the screen will awaken from sleep mode.
I then ejected the SD card and edited the config.txt file in Notepad on my Windows laptop to comment out the line I had added (using #). When I then inserted the SD card to the Pi and started it up it was ok again (though with the screen in the normal position due to the rotation code being commented out).
I have since tried editing the config.txt file in the following ways, always with the same result as above:
- using nano in Super User mode as suggested above (typed su in main Pi terminal, edited the config.txt file in nano as above then typed exit to exit su mode)
- using notepad on my laptop
- using LXTerminal on the Raspbian desktop and using nano from there
Again with all of these commenting out the line always fixes the problem and the Pi then boots as normal.
I have spent quite a long time tryingto rotate the screen with no progress at all, and I need to rotate the screen for the project I have planned.
- brand new Pi (512 MB)
- Installed latest Raspbian Wheezy (25th May 2013)
- Tried to rotate screen only (nothing else changed or installed, etc...)
- Won't reboot after editing config.txt file by adding one single line (display_rotate=2)
Please let me know if anyone else is having a similar problem. Any advice or guidance greatly appreciated, again apologies if I'm missing something fundamental here but I've only had the Pi for less than a day!
Edit: I should probably have mentioned that I'm using a HDMI to VGA adapter. This works fine without editing the config file. I have also tried the same method above without the VGA adapter and running the HDMI cabble straight to a HDTV, works fine with the code commented out but then doesn't when I uncomment it.