USB GPS

[pmprog]

Has anyone tried a USB GPS on the Pandora? Does it work through Android as well?

I was looking at something like this:

http://www.amazon.co.uk/GLOBALSAT-ND-100-Receiver-NetBook-Notebook/dp/B00286KXGU/ref=sr_1_1?s=computers&ie=UTF8&qid=1383228337&sr=1-1&keywords=usb+gps+receiver

They talk about drivers, but surely it just provides a COM port for passing data?

 

[ekianjo]

i only have a bluetooth one - a nokia model, and it works fine. for USB, i guess it should work as well if it's supported by Linux drivers.

 

[pmprog]

Well, you can download Redhat drivers, which is a zip that contains one .c file, a makefile, and a readme. Not sure how that would work through Android though.

Anyway, I've ordered it, and guess I'll see how I get on

 

[DAP]

The biggest issue is that USB GPS devices are USB "Full Speed" devices that will not work directly with the large USB port. To use it, you will need either a USB OTG cable, mini-A to mini-B, or Micro-B, depending on what the GPS uses, if it has a hard wired cable, you will need a mini-A to full sized A adaptor. Or you will need a USB "High Speed" hub to connect between the large connector and the GPS.

 

[ekianjo]

The biggest issue is that USB GPS devices are USB "Full Speed" devices that will not work directly with the large USB port. To use it, you will need either a USB OTG cable, mini-A to mini-B, or Micro-B, depending on what the GPS uses, if it has a hard wired cable, you will need a mini-A to full sized A adaptor. Or you will need a USB "High Speed" hub to connect between the large connector and the GPS.

what do you call full speed? usb 2,0?

 

[slaeshjag]

Full speed is 1.1. Hi-speed is 2.0

 

[ekianjo]

Full speed is 1.1. Hi-speed is 2.0

Please use numbers then, "full speed" is really confusing. 

 

[Binky]

Full speed is 1.1. Hi-speed is 2.0

Please use numbers then, "full speed" is really confusing. 

Problem is that USB2.0 includes all of low-speed, full speed and high-speed.

Stupid naming, but it really is more precise to use names.

Why should GPS receivers be high-speed anyway? They're serial devices really.

 

[hedwards]

Full speed is 1.1. Hi-speed is 2.0

 Please use numbers then, "full speed" is really confusing.

 Problem is that USB2.0 includes all of low-speed, full speed and high-speed.

Stupid naming, but it really is more precise to use names.

Why should GPS receivers be high-speed anyway? They're serial devices really.

That's half true. USB 2.0 ports usually have chips for both the 1.1 speeds and another for the 2.0 speeds. AFAIK, the Pandora was designed in a way that it won't offer 1.1 speeds on the non-to-go port but will on the USB-to-go port. Unless I have that backwards in which case reverse that.

I'm not sure why a USB GPS receiver would be USB2.0, a lot of those devices worked just fine over a serial port connection, so I would wager that something is reversed here.

 

[Binky]

That's half true. USB 2.0 ports usually have chips for both the 1.1 speeds and another for the 2.0 speeds. AFAIK, the Pandora was designed in a way that it won't offer 1.1 speeds on the non-to-go port but will on the USB-to-go port. Unless I have that backwards in which case reverse that.

That's why its more precise to use names.

As I said,

USB2.0 includes all of low-speed, full speed and high-speed.

The Pandora's full-size port is not USB2.0 - it is purely USB high-speed

 

[DAP]

Full speed is 1.1. Hi-speed is 2.0

Please use numbers then, "full speed" is really confusing. 

Having designed several USB devices, I will NEVER use the version numbers when I wish to describe the speed of a USB device. The numbers do not tell you the speed of the device.

USB 1.0 and USB 1.1 support "Low Speed" and "Full Speed"

USB 2.0 supports "Low Speed", "Full Speed" and "High Speed"

USB 3.0 supports "Low Speed", "Full Speed", "High Speed", and "Super Speed"

As you can see, I can make a "Low Speed" device and call it "USB 3.0".

The speed names are the only thing in the specification that have any meaning when referring to the speed the device is capable of.

The mistake that was made in the design of the Pandora is that the port they connected to the USB A connector was intended to be hard wired to a High Speed hub. Part of the specification of a high speed hub is that it is required to translate low speed and full speed transactions into high speed transactions. It is a violation of the USB 2.0 specification to not support low speed and full speed on a USB port. If you really know what you are doing, and aren't planning on selling your device to the public, you can get away with what was done on the Pandora. If you do this and sell it to the public, you will be endlessly explaining to your customers why the USB port is not working and how to work around the bug.

The USB A port on the Pandora is NOT a USB 2.0 port, it is a USB High Speed port.

 

[pmprog]

Interesting detail there DAP, thanks.

I always loved how "Full Speed" is no longer the fastest. Just like how "High Def" TV is only HD to the previous resolution, what's next "Super HD", "Mega HD", "UltraDef"?

 

[Binky]

Maybe they should have gone Low --> high --> super --> hyper or something?