When is a USB charger *not* a USB charger?

Answer: When you want to charge an original PS3 SixAxis controller.

I’ve had an original first-release PS3 since 2007, and it’s a fine piece of kit. Given that it was designed many years ago, it’s lasting extremely well. In my case I mostly use it for streaming my video collection from my (DNLA-enabled) home server, where I store my digitised DVD collection, to the main TV, which is attached to the PS3 by HDMI.

My only problem with this arrangement is that I’ll often find that when I want to use the PS3, the rechargeable wireless controller is flat, thanks to extended movie-watching by my kids. The only way to recharge the controller is to plug it into the USB port of the running PS3, which charges it up again reasonably quickly.

So I decided it would be worth spending the £5 or so to get a mains-powered USB-charger, so the controller can be left permanently on charge when not in use, so it’s always fully charged when needed. A fine idea.

Except in practice my PS3 controller fails to charge when plugged into the mains charger. It charges when connected to the PS3. Or my laptop. But it also fails to charge on my old mains-powered Blackberry USB charger. Something is definitely odd.

There are now extensive specifications for how you must go about powering (and especially charging) devices via USB, but back when the PS3 was designed (2003-2005) this was something of a new and grey area, so it’s not at all clear that Sony would be following the current specifications. And so it transpires.

Unlike almost every other device out there, which either just draws current from the USB port without asking, or follows the specifications and passively checks for fixed voltages on the USB data lines, my PS3 controller will only start charging after it has been both connected to, and enumerated by, a host USB port.

What this means in practice is that my PS3 controller can only charge from a real USB port on a computer that is capable of intelligently communicating with it. Modern mains-powered USB chargers which describe their capabilities according to the USB specifications using voltages and simple resistances between the data lines will never persuade it to start charging. Which is very annoying.

So, the question is, will newer PS3 controllers follow the new USB specifications, or will they also require enumeration before they can be charged? I have a suspicion that the newer controllers will follow the new USB charging specifications; this would account for the number of very mixed reviews of “mains powered PS3 controller docking stations” on places like Amazon. Anyone with an old original controller like mine, and a new docking station designed to the USB standard will find it doesn’t work. Whereas people with newer controllers will see it work perfectly, and not understand the poor reviews from the owners of original controllers.

I’ll find out soon enough, as I’ve ordered myself a Dualshock controller for Christmas to allow my kids and I to play some games head to head.

If that follows the recent USB specifications then I think my low-tech solution will be to leave the original controller connected to the PS3 USB port, and predominantly use the new controller. The original will charge whenever we use the PS3, and the new one can be plugged into the mains-powered USB charger and charge when the PS3 is switched off, and so also always be ready for use.

If the new controllers do not follow the new USB specifications then there is a solution to the problem – build a charging circuit that is capable of supplying power from the mains that can follow enough of the USB specifications to properly enumerate the controller. Fortunately, someone has already done all the hard work for a single controller, and published the information. I’ll need to modify it to support (at least) two controllers, which will need some simple circuit changes to add more USB ports, and some more extensive changes to the microcode to provide support for them.

Since I’ve not played with micro-controllers yet, I’m going to hold off from attempting this until I definitely know I need it!

My new DualShock3 controller arrived today. It also refuses to charge on a standards-compliant USB charger. Options are to build something to resolve it, as detailed earlier, or pay the outrageous markup that Sony demand for their charger, which can enumerate the controller. I suspect I won’t be able to build a charger for less than the cost of Sonys commercial charger, so I may as well just go and buy it. But I do feel cheated by this. Sony ought to have fixed their controllers by now.

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