I'm looking to create a device that acts as a host to a USB peripheral, format the data, then send it out to another host (the PC). Are on-the-go chips capable of accomplishing this or would you need to implement both a host USB microcontroller and a peripheral USB controller? I don't see much information out there for creating a middleman that performs data molding for USB prior to reaching a host. Any information would be appreciated, hopefully I didn't butcher this concept.
you should use a microcontroller with 2 USB busses.
One should act as a host, and the other as a slave.
You will need to implement them both.
USB OTG is used to create a host and a slave in 1 device with 1 connector,
so it's impossible to use them together at the same time.
I'm trying to build a device to read the current GPS coordinates. The device will include a small computer inside running Windows 7.
I'm looking for a usb GPS to connect it to the computer and be able to read the GPS coordinates from my VB.net 2010 program. Of course, here the most important thing is what hardware I need to accomplish that. Suggest me some GPS models.
Do I need only a GPS receptor or do I need even more hardware?
In addition to jcibar's answer:
For Bluetooth GPS or most USB devices you probably don't even have to set the classic RS232 communication settings like "baud rate". It will just work, whatever baud rate you set.
Look at the "Ports (COM & LPT)" list of the Windows Device Manager - One of the "COM" devices listed should be the GPS receiver and it many times includes a description that indicates what it is.
E.g. on my Win7 x64 notebook I have a "Sierra Wireless Gobi 2000 HS-USB NMEA 9001 (COM8)" port, which is the notebook's built-in GPS. It will just start communicating the moment I open the port:
17.09.2013 10:12:01.890 [RX] - $GPGSA,A,1,,,,,,,,,,,,,,,*1E<CR><LF>
$GPGSV,4,1,16,10,,,,21,,,,20,,,,32,,,*7A<CR><LF>
$GPGSV,4,2,16,31,,,,30,,,,29,,,,28,,,*78<CR><LF>
$GPGSV,4,3,16,27,,,,26,,,,25,,,,24,,,*79<CR><LF>
$GPGSV,4,4,16,23,,,,22,,,,19,,,,18,,,*7E<CR><LF>
$GPGGA,,,,,,0,,,,,,,,*66<CR><LF>
$PQXFI,,,,,,,,,,*56<CR><LF>
$GPVTG,,T,,M,,N,,K,N*2C<CR><LF>
$GPRMC,,V,,,,,,,,,,N*53<CR><LF>
You can use any serial COM port / RS232 logger to test this.
You can use any GPS (USB, Bluetooth) that provides a RS232-level serial interface (serial port). The GPS will create a virtual serial port (e.g. COM13) that you can use in your VB.net program to read serial data (NMEA frames tipically at 4800 bauds).
For instance, for USB you could use something like this: Haicom HI-206USB.
I'm developing an embedded USB device which needs to be available to two different hosts.
The first is a normal PC, where it will be used as a MSC (mass storage) device, and the second is a specific hardware which the USB device needs to comunicate with a CDC profile.
during the enumeration, the USB device send descriptor table where it declares its capabilities.
Is there a way in the enumeration process to know to which host the device was connected to ?
The simplest solution perhaps would be to implement a "USB Composite Device", where the single device presented both the MSC and CDC class interfaces simultaneously. The host PC would see both interfaces, but you could simply leave one unused. The "specific hardware" would probably simply ignore the MSC class if it had no support for it.
I am trying to access an USB HID device under Ubuntu(kernel-3.0). I want to write a program which could notify me whenever an USB device is attached to the bus i.e is there any event generated whenever an USB device is plugged in which I can monitor. I have looked into DBus and HAL without any success. But I don't want linux to load its current modules(USBHID and HID) when the device is plugged in. I also want to ask if the mentioned modules are also the device drivers used for HID devices.
My sole purpose is to run a script whenever an USB device is plugged into the bus which will indirectly call the above mentioned modules.
I am writing my code in C. I am quite new to linux. So it would be of great help if anyone could point me in the right direction.
Thanks..
The UDisks deamon will send the D-Bus signal "DeviceAdded" when a USB drive is inserted, and probably another "DeviceAdded" for each partition on the drive. If you have automount you would also get a "DeviceChanged" signal when the partition(s) are mounted. You can then query the UDisks interface, as well as individual devices about their properties, for example. You can find more info on the UDisks interface here: http://hal.freedesktop.org/docs/udisks/UDisks.html
One way to get more familiar with what goes on with block devices (or whatever) on D-Bus, is to install and use D-Feet to inspect the bus. UDisks appear on the System bus. You can see what is there and inspect the properties for individual devices as well as the UDisks interface itself.
Another way, which would also allow you to see what signals are transmitted on the bus, is to run dbus-monitor from the command line.