When you plug your headset in, its not a usb port at all. Its straight analog audio. (Take a closer look, there are 10 or so pins. There is even a pinout diagram floating around, and 3way headset adapters that allow usb data, headset audio and charging..)
At the end of the day, usb host/guest is NOT interchangable without hardware modifications. There is some good news here - rumours are that the g1 has a usb-otg capable chipset. With 'magic' bit flipping (as in, the info has to come from htc/qualcomm) and some minor hardware hacking (5v supply, similar to what n770/n800/n810 needs) you can get usb host working. (That 'minor' hack may be less minor if there is a diode in the way, since it'd require soldering onto the board instead of just building an adapter.) On Fri, Jul 10, 2009 at 4:16 AM, Nicholas Radford<[email protected]> wrote: > The phones usb port is not a guest when I plug my headset into it. > > It is when I plug my computer into it, but thats less of a guest / host > situation and more like mutual devices chattering to it each other. > > USB in just a serial bus at the end of the day. If one end has to be a host > and the other a guest, this can change based on which configuration, non? > It's not like USB are hardwired to be either host or guests, that's a > progmatic thing, decided by the two devices in question. > > On Fri, Jul 10, 2009 at 7:10 AM, Tony Su <[email protected]> wrote: >> >> Unless someone can answer definitively based on the phone's technical >> information, >> >> Based on observation only, it's not possible based on general USB >> architecture. In any USB connection, one endpoint is designated the Host and >> multiple guests can connect to that Host (IIRC theoretically 256 devices). >> >> Because the Phone can connect to the USB port of a computer, the computer >> is always the Host and anything else that can connect is a Guest, so the >> Phone's USB port is a Guest. >> >> A Sensor would also be a Guest so cannot connect to the Phone, it needs to >> connect to a port configured as a Host. >> >> Tony >> >> ----- Original Message ----- >> From: Mas <[email protected]> >> Sent: Wed, 7/8/2009 12:12pm >> To: Android Beginners <[email protected]> >> Subject: [android-beginners] USB data acquisition >> >> >> Hello, >> >> I am doing a feasibility study using an Android Dev phone. I want to >> attach the phone using the USB cable (or the serial port) to a sensor. >> In an application, I want to pole the sensor over the cable and have >> the resultant value displayed on the screen. The interaction between >> the sensor and the phone would involve the phone sending down a >> request data byte and the sensor responding with the necessary data. >> Is a data acquisition application of this nature possible on the >> phone? >> >> Thank you for your time, >> Mas >> >> >> >> > > > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Android Beginners" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-beginners?hl=en -~----------~----~----~----~------~----~------~--~---
