USB Host Comes To Zipit

This USB to Zipit Dock adapter and a special kernel makes USB host mode for the Zipit possible. Previously, the cheap and hackable wireless client needed a hardware modification to enable USB support. The new kernel bootloader, called U-Boot, makes the internal alterations unnecessary (see the demo after the break). Now the only caveat is one of voltage. Zipit only supplies 3.3V when running on battery so your choices are to only use USB when the Zipit is plugged into a charger, or use a powered USB hub. But if you’re already building a hub adapter it shouldn’t be too much trouble to add in the option for a battery-powered hub.

So can we play our NES games using a USB controller now?


[Thanks Geordy]

26 thoughts on “USB Host Comes To Zipit

  1. From the blog post: “The full featured U-Boot bootloader replaces the original Z2’s blob bootloader. With U-Boot, you can run scripts at boot time that check for and run applications, kernels, etc from locations in flash or an SD card.”

    So the above comments are correct, it isn’t a kernel, but rather a bootloader that allows the initialization of the USB host drivers, something which was not previously possible… it seems.

    The Zipit seems to be a fair buy at $40-$60, then another $5-10 for that custom USB hub. Hell I’ve seen portable knock-off gaming devices for more than that.

  2. In one expectation we’d reasonably expect that USB devices like Drives, Wi-Fi, Keyboards etc would be potentially usable this way. IF that’s made a reality, these boxes may become a lot more useful.

  3. Before mozzwald got ahold of the USB Host information GPSFan had already tried keyboards, mice and a thumb drive and they all worked wonderfully. The wifi dongle he tried partially worked but that was many kernels ago so the situation might be better. The only things he didn’t try and confirm worked were USB LCD displays and they will probably not work or probably not work well as the majority of the ones I have found are USB 2.0

  4. poor zipit creators. they have probably never sold their overpriced messaging plan. i like to watch the progress. when it gets useful enough i’m gonna buy a few. otherwise its android tablets 4 teh keedz

  5. @jeditalian
    If anything, the ZipIt 2 has gone exceptionally well for them. They knew there was a strong following for the original ZipIt in the hacking community, so they capitalized on that with the second version of the hardware by opening up as much of it as they could. It’s a powerful, easily extendable, and above all else cheap, platform to work with; so hackers buy them up.

    At the same time, they are still selling the device to parent’s and teenagers who have no idea about the other community that has developed around the hardware.

  6. No, U-Boot hardware init has nothing to do with Linux kernel hardware init. The only thing U-Boot has to do is init the DRAM correctly and load and execute the Linux kernel from some memory media.

    The rest (init of PXAUHC etc.) is solely up to Linux kernel.

    Though on other devices, it’s possible to use PXAUHC even in U-Boot.

    I didn’t add this PXAUHC support into mainline Z2 Linux kernel source nor U-Boot source (which this uses) as this is non-standard hack.

  7. Wouldn’t it be rather trivial to add a boost converter to the “USB to Zipit Dock Adapter” they mention in the original article? That way, you could have 5V (though probably quite low current, but might be enough for a keyboard / USB stick)

  8. man I remember going to all the target stores in my area looking for one of these. Never got to find one.
    Couple questions, doesn’t the z2 already have wifi? Why would you need to use wifi through usb?
    Can you hook up two thumb drives to the hub and copy between the two?
    And can it run freenas?

  9. Before I toss my “using this hack” comments in- I have to mention an often overlooked aspect- We’re all dependent upon the kindness of folks who have worked hard at unlocking this hardware’s functionality. And we need to share reports about our projects using their code..

    That’s said also to remind us about how important feeding back our user reports can be. The developers of software that unlocks devices cannot try their code with all of the USB stuff in the world. So- our reporting pass/fail reports about USB stuff to developers that ask us to- is a Very Good Thing. Both for the developers and everyone else.

    Moving on to my idea for using the unlocked Zipit.

    I have a 2gb music player/FM transmitter that’s built into a case style like a phone’s car charger. Micro Center often sells open box returns of similar units for<$20. It has a USB port for song loading/playing music from Flash Drives. If it would be interoperable= controllable- with the USB Host modded Zipit? Then it might be used to have a FM transmit output from the Zipit. I do accept that some of the details will be non-trivial. But if it were trivial, it might not be worth space here.

    There's a few "interesting" social hacking applications for a compact WiFi remote controllable FM transmitter.

  10. Regarding the DC-DC converter hack, I’ve been trying to do this and have not been able to get it to work properly. One MAJOR problem I have with the DC-DC converter is that if I hotplug the dongle into the back of the Zipit, the whole device dies. I’m assuming this is from a voltage drop but I’m not sure. Even without the hot plugging though, I’ve still not been able to make it work for some reason. I DID however find a DC-DC converter with nearly perfect specs that is small enough to fit into the expansion connector housing. And I disagree about murdering the battery life. If you are just using some low power device such as a USB memory key, the dc-dc converter won’t be drawing very much current. Remember that’s one of the benefits of switch mode power supplies. Here is a picture of what my adapter looks like

  11. @Geordy, it’s cute to say switched uses less power, but there’s a relationship between voltage and power you know, 60mA of 3.3v is not the same as 60mA at 5v, and 5 volt is 1.5 times 3.3v, so you don’t only have the loss from the conversion circuitry but you need to count on the reality that what may seem a low/doable (milli-)ampere use on 5v is a much higher pull on 3.3v from its perspective, and I’m sure the battery on that thing has severe limitations.

    But I guess it can’t harm to give it a shot, and you can also mod the battery of course, install something beefier, or double them.
    And I like your hacking attempts.

    Another idea though might be to use the powerinput and connect a battery to that, you’d still be running on batteries but the device will think it isn’t and that way you get the 5v on the USB and have a longer batterylife, then you’d need to build a nice case-attachment and a charger though.

  12. @Mike, that’s a good point about 3.3v vs 5v being much different amperage-wise. I’ve not tried measuring the amperage between the boost converter and the Zipit yet but I think that would be a good next step to see what it’s actually pulling. I certainly wouldn’t try to power a hard drive or even a hub off of that dc-dc converter but a small memory device or even a mouse SHOULD work. The device as shown in the picture DOES seem to work as far as power is concerned. I think my problem with devices not recognizing stems from a grounding issue or something more along those lines. The expansion port was originally designed with an add on camera peripheral in mind although I’m sure that design worked on the 3.3v.

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