Pandora usb 2.0


padoro

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Oct 28, 2012
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Please, could someone explain me why the Pandora uses a usb 2.0 port when most mouses and keyboards uses 1.0? It's most frustraiting trying such a simple task as conecting a mouse to work with it...
 
Because if it were just USB 1, you would be furstrated by the slow as hell tranfert rate when connecting a USBKey / HardDisk.

Anyway, the small USB Port is USB1 compatible natively (ok, you need an hard to find adapter for it).

And, if you want to connect both a mouse and keyboard, you need an USB Hub, that will take care of the USB1->USB2 issue.

(but yeah, it is an annoying problem, but with many workaround).
 
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Yes I've tried, but going to local shops it is dificult to find it. It is easy to find micro usbe otg but not mini usb otg. At least in my area.


I could use a hub but don't want to add too many peripherals and it must also be an specific one, doesn't it? High speed
 
almost every USB I saw was high speed... I've yet to see another one, I could imagine there's still some left for the "before USB2.0 era" but all cheap common USB hubs are USB2 nowaday...
 
Ok thank you, I will try with a hub. Sometimes I miss a mouse to use with the Pandora though it's not a big issue.
 
Please, could someone explain me why the Pandora uses a usb 2.0 port when most mouses and keyboards uses 1.0?
The OMAP3 chip has two USB channels: one is USB2.0 only, unfortunately; the other has support for both USB1.0 and USB2.0 but it is also the OTG port. They could have used that port as the full sized port but they they wouldn't have an OTG port.See, USB2 is not directly backwards compatible with USB1, it is on desktops because there's a translation chip in between which can understand USB1 and convert it to USB2 commands. When it came time to design the Pandora there was an attempt to put the same circutry into it so that the full sized USB port would also be backwards compatible but ultimately it had to be scrapped, there just wasn't any room on the board. The decision to cut it was unfortunate but necessary. Designing a system like this is all about compromise: you have very limited features in your choice of processor, and limited space on the board if you want to expand on those features.

I believe the OMAP5 which is being used in the Pyra doesn't suffer from this problem, it's ports contain the necessary parts and are fully backwards compatible (but please don't quote me on that, it's possible I'm wrong).
 
Thank you WizardStan. A very detailed answer. Now I'll not be so annoyed by this issue, I understand the reasons.
 
The OMAP3 chip has two USB channels: one is USB2.0 only, unfortunately; the other has support for both USB1.0 and USB2.0 but it is also the OTG port. They could have used that port as the full sized port but they they wouldn't have an OTG port.
Curious, but why put the preference on OTG? What does OTG give you above a standard USB port? From my viewpoint, have fullsize 1.0/2.0 beats having to buy and carry more hardware
 
OTG ports can be used as host or client ports - I think it's to do with who powers who, but I may be wrong on that.  As far as I can remember, the only reason you'd want a Pandora in client mode is for charging, and for Mass Storage mode, but I may be wrong again.
 
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Have the mini USB as client - charges off the PC, and provides mass storage etc. and have the full size as the host with 1.0/2.0 support which powers whatever's connected.

I don't see why having an extra cable on the miniusb so you can connect a 1.0 keyboard (fullsize usb) makes sense, when there's already a port there
 
Don't forget the pandoras can also be a USB HID (keyboard, mouse,etc)  when connected in slave mode.
 
Have the mini USB as client - charges off the PC, and provides mass storage etc. and have the full size as the host with 1.0/2.0 support which powers whatever's connected.
You can't. OTG means it can operate as host or client, if it were full sized to make it fully backwards compatible we would not have had a client port at all.The one port is OTG and backwards compatible, the other is 2.0 and host only.

It makes sense because there was no other way, it was this or nothing.
 
You can't. OTG means it can operate as host or client, if it were full sized to make it fully backwards compatible we would not have had a client port at all.
Ah, right, I understand now. Sorry, bit slow :)
 
I believe the OMAP5 which is being used in the Pyra doesn't suffer from this problem, it's ports contain the necessary parts and are fully backwards compatible (but please don't quote me on that, it's possible I'm wrong).
Sorry for quoting you on it, but I hope this is true.  I have a USB 2 hub I love that will probably only be used for HIDs, and some older stuff, after I build my next computer.  It gets power from the computer USB port, not by a power cable.  It would be cool to be able to swap it between my computer and Pyra without having to move everything around, and have my keyboard, trackball and controller ready to go by just plugging it in.  Of course, we could get a Pyra dock so the display cable and everything is also taken care of.
 
I believe the OMAP5 which is being used in the Pyra doesn't suffer from this problem, it's ports contain the necessary parts and are fully backwards compatible (but please don't quote me on that, it's possible I'm wrong).
Sorry for quoting you on it, but I hope this is true.  I have a USB 2 hub I love that will probably only be used for HIDs, and some older stuff, after I build my next computer.  It gets power from the computer USB port, not by a power cable.  It would be cool to be able to swap it between my computer and Pyra without having to move everything around, and have my keyboard, trackball and controller ready to go by just plugging it in.  Of course, we could get a Pyra dock so the display cable and everything is also taken care of.
That scenario would be possible anyway, just like it is possible on the Pandora. The Pandora problem is that its full-size USB 2.0 port is not backwards compatible with USB 1.0 or 1.1, which means that if you plug in a USB 1.0 device like a keyboard, it does not work. If there's a USB 2.0 hub in between, it works because the hub will convert the USB 1.x to 2.0.

So on the Pyra your scenario would work anyway -- the Pyra has two full-size USB 2.0 ports. The question is whether they also support USB 1.x, without needing a hub. And the answer is yes, at least that's what I've always understood.
 
I have a solution that works quite well.  Bluetooth keyboard and mouse.
 
I have a solution that works quite well.  Bluetooth keyboard and mouse.
Won't work for me.  I prefer wired, and I am not switching over to a lesser (probably rubber dome) keyboard merely for convenience.
 
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