Wednesday, May 9, 2012

DVD drive unable to read discs

We hadn't used the DVD drive on our computer for a while (likely since an Ubuntu upgrade) and discovered recently that it was unable to read discs. I was able to find this discussion, which pointed out that Ubuntu 11.10 has a problem reading discs if the DVD drive is configured as master. I opened up the computer and found that there was no way to change the master/slave setting of the drive, since it is a SATA drive. Booting back into the BIOS settings, though, I found that the DVD drive was before the hard drive in the list of SATA devices. I opened the case back up and plugged the hard drive into the SATA 1 connector on the motherboard. Booted back up and the DVD was instantly recognized. Success!

Friday, January 13, 2012

Re-recognizing an internal SD card reader

Last week I accidentally hit the "Safely Remove Drive" option instead of the "Eject Disk" option for my internal SD card reader in Ubuntu. After doing this, I could not get the computer to show the card reader, even after following forum advice to unload and reload modules and at last resorting to a reboot.
I recently picked up a cheap used usb video-in device, and when trying to get it to work in Ubuntu I tried running lsusb to find out if the device was recognized. lsusb took a long time to run, and when I checked dmesg I saw a number of errors of the form
device descriptor read/64, error -110
Searching on Google turned up this page, where users reported that shutting down and unplugging the system fixed their problem. I gave it a try, and sure enough it worked. I'm posting this because I didn't see anyone suggest this fix for the problem caused by using "Safely Remove Drive". Hopefully someone else with the same problem can find the solution here.

Friday, January 6, 2012

Segfault write-up

I finally got around to documenting some info about my homemade balancing scooter. See here.