Posted by Deliverator on June 18th, 2006
One of the last remaining legitimate sources of complaint about the 3rd party Rockbox firmware for the iRiver H300 series mp3 players has been the rather abysmal battery life compared to the official, manufacturer supplied firmware. Nobody could seem to figure out where all the power was going to until one enterprising Mistic River forum user took a radio shack digital thermometer and held it up against each chip on the H320’s circuit board while performing various normal player functions. It was discovered that the USB host controller chip for the “USB On The Go” / DRM Media Transfer Port was being supplied with full power all the time under the rockbox firmware, while under the manufacturer supplied firmware this chip was held in a housekeeping/suspend mode almost all of the time. Just how much power was this chip using? The best estimate is that this chip was using as much power as the main Coldfire cpu. The developers finally figured out how to suspend this chip and now battery life is much improved. How much improved? Aside from the USB host chip issue, the Rockbox firmware is much more intelligent about how it uses power than the official firmware. For instance, Rockbox caches the directory/file tree information to ram, so that the mere act of deciding what to listen to next doesn’t spin up the hard drive (one of the biggest consumers of power). Rockbox also shuts down the LCD screen, not just the backlight after the controls haven’t been touched for a while (interval is user selectable). Users have been reporting better than 20 hours on the old, 1300mah manufacturer supplied batteries. These aren’t just anecdotal observations, they are rigorously logged using Rockbox’s Battery Benchmark Plugin. Using better batteries, such as the aftermarket 2200 mah batteries sold by Newertech, users are reporting as much as 35 hours of battery life off a single charge!
I have been using my iRiver quite a lot lately, mainly to listen to podcasts during my evening walks. The original battery isn’t quite what it used to be, so I think I will purchase a new one. Replacing the battery scares me a bit, but Galan replaced one in his H320 a while back without killing his, so I feel a bit more confident about taking a stab at it. Now that the battery issue is tackled, the only thing left for Rockbox to do is add video support.
addendum I went ahead and purchased one of the NewerTech 2200 mah batteries from minidigital on eBay. They appear to be one of the only places to get these batteries. The battery is shipping from down under, so it might take a while to get here.