Usb 1.1, 2.0, Otg. What's The Diff?

[Squidge]

Yeah, great idea, but that's yet another item that would bump the cost up even further.

I can buy a complete hub which includes the connecting cable, 4 USB sockets, PCB, plastic shell and packaging for £2, so the chip itself would most likely be less than 50p, maybe even less when ordered in thousands. Considering the number of discussions on the topic, I think it would have been worthwhile.

 

[DesktopMan]

Seeing as how there will be hordes of people not understanding why their keyboard / mouse isn't working, I agree with Squidge, totally worth the cost. It might even have allowed two regular ports, which I would gladly have payed £20 more for.

 

[hch]

The ONLY way that some devices (those that require more than 100 mA, and do not work at High Speed) will work on the Pandora is if you use a POWERED (meaning it has its own power supply (wall wart, or battery pack)) hub.

But honestly, which devices these days are not hi speed and use more than 0.1A? (yeah, a usb vacuum cleaner or desk lamp, but they are fine anyways i guess ) mouses or keyboards son't usually drain more power and any mass storage without hi speed is excessively painful (i have a zaurus which only has usb-otg 1.1 and this is probably the thing that hurts most).

 

[DAP]

The ONLY way that some devices (those that require more than 100 mA, and do not work at High Speed) will work on the Pandora is if you use a POWERED (meaning it has its own power supply (wall wart, or battery pack)) hub.

But honestly, which devices these days are not hi speed and use more than 0.1A? (yeah, a usb vacuum cleaner or desk lamp, but they are fine anyways i guess ) mouses or keyboards son't usually drain more power and any mass storage without hi speed is excessively painful (i have a zaurus which only has usb-otg 1.1 and this is probably the thing that hurts most).


The GPS devices that I have looked at all use full speed, and when I have been able to find the power usage, it works out to 120 mA, so yes this is a problem.

 

[Loon]

This is the best solution I've found to the Pandora USB problem.

Belkin Hub

Reckon a talented modder could knock up something a little more elegant!

 

[cbox]

Does anyone know if mini-usb to mini-usb cables exist? I have a 2.5 inch laptop in an external case that has a mini usb connector on it, seems like it would be convenient to be able to plug it directly into another mini USB port without using a converter.

 

[Chip]

This is the best solution I've found to the Pandora USB problem.
This is the best solution I've found. Solves 99% of all your low speed device issues for only $5.

 

[DAP]

This is the best solution I've found to the Pandora USB problem.

Belkin Hub

Reckon a talented modder could knock up something a little more elegant!



That will work, but you will need a REALLY long extension cord to keep that hub powered when you are using the Pandora with a GPS mouse on a hike.

 

[Karel Jansens]

This is the best solution I've found to the Pandora USB problem.

Belkin Hub

Reckon a talented modder could knock up something a little more elegant!


I have this one from Targus:

http://www.targus.com/Uk/product_details.asp?sku=ACH65EU

Although sometimes it's just a little too compact: My older (and bulkier) USB sticks won't fit side to side.

 

[DAP]

This is the best solution I've found to the Pandora USB problem.

Belkin Hub

Reckon a talented modder could knock up something a little more elegant!


I have this one from Targus:

http://www.targus.com/Uk/product_details.asp?sku=ACH65EU

Although sometimes it's just a little too compact: My older (and bulkier) USB sticks won't fit side to side.


That one is in violation of the USB spec. (unpowerd and has more than 2 ports). On top of that, unpowered hubs are only allowed 100 mA/port whereas powered hubs are allowed 500 mA/port.

It may work anyway as quite often cheap USB hubs leave out all of the over current detection circuitry.

 

[hch]

The ONLY way that some devices (those that require more than 100 mA, and do not work at High Speed) will work on the Pandora is if you use a POWERED (meaning it has its own power supply (wall wart, or battery pack)) hub.

But honestly, which devices these days are not hi speed and use more than 0.1A? (yeah, a usb vacuum cleaner or desk lamp, but they are fine anyways i guess ) mouses or keyboards son't usually drain more power and any mass storage without hi speed is excessively painful (i have a zaurus which only has usb-otg 1.1 and this is probably the thing that hurts most).


The GPS devices that I have looked at all use full speed, and when I have been able to find the power usage, it works out to 120 mA, so yes this is a problem.


Then why not use one of these

http://www.bixnet.com/5vps2powercord.html

with one of these

http://cgi.ebay.de/Adapter-mini-USB-Stecke...1742.m153.l1262

usb1.1 with 0.6A. i guess that makes everyone happy.

i know this is slightly clunky, but these are standard pieces (i accumulated both of them somehow). i guess with a bit of soldering you can make a small adapter that should be nice, too.

 

[DAP]

The ONLY way that some devices (those that require more than 100 mA, and do not work at High Speed) will work on the Pandora is if you use a POWERED (meaning it has its own power supply (wall wart, or battery pack)) hub.

But honestly, which devices these days are not hi speed and use more than 0.1A? (yeah, a usb vacuum cleaner or desk lamp, but they are fine anyways i guess ) mouses or keyboards son't usually drain more power and any mass storage without hi speed is excessively painful (i have a zaurus which only has usb-otg 1.1 and this is probably the thing that hurts most).


The GPS devices that I have looked at all use full speed, and when I have been able to find the power usage, it works out to 120 mA, so yes this is a problem.


Then why not use one of these

http://www.bixnet.com/5vps2powercord.html

with one of these

http://cgi.ebay.de/Adapter-mini-USB-Stecke...1742.m153.l1262

usb1.1 with 0.6A. i guess that makes everyone happy.

i know this is slightly clunky, but these are standard pieces (i accumulated both of them somehow). i guess with a bit of soldering you can make a small adapter that should be nice, too.


There is a bit of a risk involved with doing this. If I read the information about the IC used for the USB OTG port, that part generates its 5V output via a switched capacitor charge pump. I'm not sure where the standard USB port gets its 5V, but I don't think I'd want to connect them together. That could really confuse the electronics possibly ending up in smoke.

If I were to do something like this, I'd hack that mini-A to A adapter to cut the VBus line. This itself may not work as USB is supposed to have control of the VBus line, and self powered devices are supposed to pay attention to its state. If that line is cut, the Pandora may try to shut down the device, and the device not seeing VBus going away may continue to drive signals onto the data lines, which is again a violation of the spec.

There no clean solution to this issue.

 

[hch]

There is a bit of a risk involved with doing this. If I read the information about the IC used for the USB OTG port, that part generates its 5V output via a switched capacitor charge pump. I'm not sure where the standard USB port gets its 5V, but I don't think I'd want to connect them together. That could really confuse the electronics possibly ending up in smoke.

If I were to do something like this, I'd hack that mini-A to A adapter to cut the VBus line. This itself may not work as USB is supposed to have control of the VBus line, and self powered devices are supposed to pay attention to its state. If that line is cut, the Pandora may try to shut down the device, and the device not seeing VBus going away may continue to drive signals onto the data lines, which is again a violation of the spec.

There no clean solution to this issue.

and how about just cutting the +5V pin in the y-adapter leading to the OTG port? now that should be absolutely safe.

actually, at this point a statement from a dev would be most welcome i guess.

 

[DAP]

There is a bit of a risk involved with doing this. If I read the information about the IC used for the USB OTG port, that part generates its 5V output via a switched capacitor charge pump. I'm not sure where the standard USB port gets its 5V, but I don't think I'd want to connect them together. That could really confuse the electronics possibly ending up in smoke.

If I were to do something like this, I'd hack that mini-A to A adapter to cut the VBus line. This itself may not work as USB is supposed to have control of the VBus line, and self powered devices are supposed to pay attention to its state. If that line is cut, the Pandora may try to shut down the device, and the device not seeing VBus going away may continue to drive signals onto the data lines, which is again a violation of the spec.

There no clean solution to this issue.

and how about just cutting the +5V pin in the y-adapter leading to the OTG port? now that should be absolutely safe.

actually, at this point a statement from a dev would be most welcome i guess.


Perhaps I did not make that clear enough, but if you look above you will see the part of the comment where I made the font bigger. The VBus line IS the +5V pin, so that IS what I was suggesting, and no it is not a good idea.

 

[sold]

For keyboard and mouse into 1 usb 2.0 port, would this work?
http://industrialcomponent.com/vigor/vad1002.html

And I was thinking, a powered usb 2.0 hub could be useful as a usb charger. I'm planning on using Dualshock 3 controllers with my Pandora so the usb incompatibility isn't going to be a problem, unless there aren't any drivers. The hub can recharge the controllers and the Pandora, and if necessary it can be used for plugging in low speed devices into the Pandora usb port as well.

If you wanna use a hard drive and a couple of wired game pads, you're gonna need a hub anyway.

 

[DAP]

For keyboard and mouse into 1 usb 2.0 port, would this work?
http://industrialcomponent.com/vigor/vad1002.html




That would be a full speed device, so you won't be able to use it on the main port without a hub. Don't know how much current it would draw, (could be a lot if you plan to use one of the IBM "clicky" keyboards). I think you are better off with a hub and USB keyboard & mouse, or spend more money with a bluetooth keyboard & mouse.

 

[hch]

Perhaps I did not make that clear enough, but if you look above you will see the part of the comment where I made the font bigger. The VBus line IS the +5V pin, so that IS what I was suggesting, and no it is not a good idea.



sorry, i did not read carefully enough. and yes, it will violate the usb specs (actually, if i am not mistaken a y-cable itself violates it as well, since you are not supposed to draw mote than 0.1A without negotiating). i still think this might work and if not there will be no smoke. would you agree?

 

[DAP]

Perhaps I did not make that clear enough, but if you look above you will see the part of the comment where I made the font bigger. The VBus line IS the +5V pin, so that IS what I was suggesting, and no it is not a good idea.



sorry, i did not read carefully enough. and yes, it will violate the usb specs (actually, if i am not mistaken a y-cable itself violates it as well, since you are not supposed to draw mote than 0.1A without negotiating). i still think this might work and if not there will be no smoke. would you agree?


No, I think there is a very good chance this will not work. This would logically connect the device to the USB OTG port that can only supply 100 mA. Even though you have connected the power supply to a port that can supply 500 mA, when the Pandora initializes the device, and the devices claims it needs more than 100 mA, the Pandora, not knowing about the power bypass, will say "Hey, this device wants more power than I can supply!" and shut down the device.

 

[Kyo]

I made it better








It even has a power in, I think I'm going to make a battery pack for it as well.

 

[DAP]

I made it better








It even has a power in, I think I'm going to make a battery pack for it as well.



Was that thing originally an unpowered hub? If so, you will need to look up the data sheet on the IC they are using. There are usually a few pins that need to be connected high or low to indicate to the hub if it is self powered, or USB powered. You need to change it to self powered if you are going to add a battery pack to it. Also be aware that USB has some rather strict voltage requirements on the USB ports, so your battery pack will probably need a voltage regulator on it.