dedicated USB OTG mouses (check for interest..)


Note that the OTG port only provides 100mA. A lot of devices I have fail to even power on when connected directly to the OTG port and the ones that do power on usually get disconnected by the driver because they ask for more than 100mA (you can check using dmesg). I have only a single USB stick that reliably powers on *and* doesn't ask for more power. But some units seem to do better than mine and the cable may be a factor in this, I don't know.
 
I wouldn't think a mouse or a keyboard would draw more than 100mA, but maybe there are poorly designed ones out there.  so far I've only had an optical mouse and a USB N64 controller plugged into my cable.. haven't tested too much else.

Edit: Maybe your adapter or OTG socket may have a defect, perhaps a resistance point causing excessive current drain. 
 
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One of the tested devices was a Yubikey, which is a tiny little device that essentially emulates a keyboard - so I'd like to think it takes very little power. On the USB-A port it lights up but then goes out a bit later, on the mini port it doesn't light at all. So far I have tested two mini-A cables now and the outcome is the same. Ideally I'd have some hardware that proves what current is being output, but I'm not a hardware person.

I'm giving up with this port - so far shoving a bit of paper in with the normal A port is enough to keep a hub firmly connected for now.
 
At some point I was thinking about making a mouse with a cheap USB hub IC so it works with USB2.0 port. I could bundle it with a small wifi dongle and such; would be perfect for desktop use.

And then I just installed a better wifi antenna and lost the motivation. But the idea still seems attractive, especially considering that I could reuse this mouse on any PC and the Pyra.

Maybe you guys should consider this option?
 
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Just wondering if anyone has had any luck with creating USB OTG mouse? The hub controller for this purpose has the appropriate specifications and certainly sounds a neat idea.
 
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I wonder what are the legal implication if I decide to produce some devices and sell them. Last thing I want is to get myself into some complex tax paperwork.
 
Same tax as any other small project I'd think - generally within allowances up to a certain level if it's not your main income.  Nothing about it being an OTG mouse should make it different to selling a normal mouse as far as the tax man is concerned I'd have thought.  Please note, IANAA.
 
What I meant is that I'll have to buy parts and then sell the mouses, so there will be some sort of accounting (revenue from selling - production costs = income subject to taxation), right? Even if there is no real income, I'll have to explain why I don't declare those sums coming from online payments. And the paperwork I'll have to provide is totally unknown to me and I don't feel like spending too much time on it.
 
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Those accounts are things you need to file if you set up a company.  You might want to set up a company so you can claim back the VAT on all the parts.  On the other hand, if you're happy paying VAT on everything then there's nothing to declare.
 
Here's a prototype I have built. It's basically a mouse with 3-port hub inside, one of which is soldered to the mouse itself. The other two ports have regular USB connectors and can be used to attach USB nano dongles. In my setup I have included a WL0084A b/g/n stick which is recognized by Pandora out of the box. The second port could accommodate e.g. a wireless keyboard receiver etc.

Here's how the mouse looks like. The photos show: 1) the assembled mouse, 2) the mouse with the top cover removed, 3) the top cover "modified" to make some space for the hub, and 4) the electrical connections closeup. The assembly also includes insulation tape isolating boards from one another, which is not present on the photo.

Although the mouse cable is only USB1 certified, the whole assembly works fine. When plugged into Pandora's full size USB port, the mouse works and the WIFI stick is detected and picks up networks. During normal operation (mouse in use, WIFI connected to a network) the device consumes about 200-300 mA from the battery. I suppose the power consumption may increase under heavy traffic.

Soldering and assembly took me about an hour (I have tried two different mice and I had to entertain my kid at the same time :) I'm still hesitating about selling those things online, mainly because I cannot guarantee that the crappy mouse cable will work reliably with USB2 for every mouse produced. But I'd like to check anyway - how many people here would be interested in such device (including the WIFI dongle) for about 20-30€ + shipping. I live near the border so I may use both German and French postal services.
 
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Besides neatness, what's the difference between using your special mouse vs. using external small USB hub and plug in the mouse and mini USB wifi stick since you have to sit on a table to use the mouse as well?
 
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