Archive for the ‘USB’ Category

Sansa e260

2008-12-15

I bought a refurbished Sandisk Sansa e260 v1 for $35 and it came yesterday. Works pretty well so far.

It has 4GiB built in, which isn’t enough for my music collection, but it also takes microSD cards, which have come down in price a great deal lately. 8GiB for about $20. So 12GiB for ~$55 and it has a color screen and a battery that lasts a while (supposedly >15h). Not bad.

I bought it with the plan to put rockbox on it (since rockbox supports microSDHC, whereas the stock firmware does not, and SDHC would be required to use an 8GiB card), but rockbox doesn’t allow charging over usb natively (you have to reboot into the stock firmware for that or for transferring files), so I might just leave it as-is for a while. The stock firmware is better than I expected it to be, but then again, I didn’t expect it to be very good a priori.

I copied 3.5GB to it and rsync said that it did 4.15MB/sec on average. Don’t forget the –no-group option if you use rsync –archive.

One complaint: It was set to the wrong usb mode out-of-the-box. There’s the usb mass storage mode (MSC) and then there’s some other mode (MTP) and for some silly reason, it’s set to the other one by default. After plugging it in to charge for a moment and then unplugging it (after checking on the computer that the drive was not mounted), the software got in a weird state where the display would update normally depending on the normal usage of the device, but immediately it would go back to display the connected-over-usb screen (even though it wasn’t) so that you couldn’t see what was going on. To fix it, I had to find a FAQ about e200 sansas that said to change it to MSC mode in the settings->usb mode thingy, which I had to do with the usb connected screen in the way, but it is still possible to navigate the menus with it like that. Then, I plugged it back in to the computer and it automatically mounted the drive. Then I ejected it and unplugged the usb cable and the sansa summarily rebooted itself (which it’s supposed to do after you disconnect it from a computer for some reason). The weird behavior went away at that point. Been fine since. I probably could have also solved the problem by just rebooting the sansa (which I didn’t know how to do at the time) or telling libmtp to let go of the device somehow, although the system log doesn’t say anything about mtp at all ever. Supposedly the MTP mode is supported in amarok rhythmbox and audacious, among other players, but I much prefer just having a storage device to drop files on as opposed to an itunes/gtkpod-like interface.

Here’s a tutorial on using a sansa on ubuntu linux for any who are interested. It basically works just like any non-linux machine – plug it in, copy files to it, unmount it, unplug it and you’re done – but there’s some good info in the tutorial anyway (updating firmware, adding album art, adding videos and pictures, install rockbox, etc).

update 2008-12-19: This is part 1 of a review of my experiences with a refurbished sandisk sansa e260. See here for part 2.

Advertisements

the perception of quality

2008-07-31

I have a Western Digital external hard drive with a USB interface and it was behaving unreliably on my laptop running Ubuntu 6 and my desknote running Ubuntu 7. It did work reliably, however, on my tower that runs gentoo linux. Unreliably, in this case, means that in the middle of trying to copy data to or from the drive, it would unmount and spontaneously remount and the file io operation would fail. I thought this meant either Ubuntu sucked or my drive was broken but worked intermittently or that Western Digital drives sucked intermittently.

Turns out it wasn’t any of those. The laptop and the desknote both provide just a little bit more current to USB devices than the tower does, so if you plug in the hard drive to the tower using just one of the two USB connectors on the split end of the cable, it doesn’t spin up and you need to plug the other one in to a second USB port for extra current. On both the laptop and desknote, the drive spins up with just the single cable plugged in (but while being used, the drive draws more power than it took to just spin the drive up and then spins itself down for lack of power and generates an error on the bus). I only realized this was the problem today when I was holding the drive when it came up with one of its buffer io errors: The drive was spinning down and back up as if it didn’t have enough juice. It’s been working reliably since I noticed this and plugged in the other part of the Y-cable.

I was ready to ship the drive back to Western Digital and uninstall Ubuntu. The FUD (fear, uncertainty and doubt) that proprietary software companies (and their minions) have spread about linux being unreliable works on an unconscious level.