Trying to come up with a serial port...
 

Does anyone know if the little connector with gold pads area near the battery compartment provides any sort of serial port? I would like to have a non-wireless RS-232C serial port (at least transmit and receive data lines) to be able to control an Icom PCR-1000 computer controlled receiver.

Thanks and best wishes to all!

Re: Trying to come up with a serial port...
 

You can use a BT->RS232 adapter, but they can be pricey.

If you really *require* non-wireless, then I guess I don't know the answer so I'll leave it up to someone else :)

Re: Trying to come up with a serial port...
 

Hmm....I would say go for the BT-to-RS232 as suggested above.
I know they've become popular of late for network admins to be able to wirelessly reprogram/reflash layer-3 switches, routers, modems, etc.
But I don't know how the N800 would interact with something like that.
Hacking will probably have to be done.

Another way around it would be to have a small computer setup next to and plugged into the receiver while running a small webserver that can host some small web pages for control. Or you can just SSH into the computer over wi-fi and run it all from the command line. Or use VNC to remotely control the PC.

Re: Trying to come up with a serial port...
 

description
http://fanoush.wz.cz/maemo/n770-internal-pinout.jpg
pinout on device
http://fanoush.wz.cz/maemo/n770-inte...t-location.jpg

Best is probably to buy any usb data cable for mobile phones, they contain serial to usb converter. Google for FBUS data cable. For real RS-232 you would need converter http://sodoityourself.com/max232-ser...vel-converter/

Re: Trying to come up with a serial port...
 

Also check
http://maemo.org/community/wiki/howt...elcompilation/
Chapter 'Serial Console'

Re: Trying to come up with a serial port...
 

Cool. I was wondering what those were for! (Assumed factory diagnostics.)

You might also consider a USB to Serial adapter (which are extremely common nowadays). Somewhere -- oh yeah, HERE -- there are instructions on how to turn your 770 into a USB host, allowing it to access peripherals like keyboards, thumb drives, and (maybe?) USB to serial adapters. (I would think that would expose itself as a regular serial port, whatever /dev/??? that translates to.)

Keep in mind that you must supply 5v to the USB cable somehow. There are a few cables out there you can purchase (like those for mini external hard drives) that allow you to inject power, or you can just splice your own. If you can solder, you will have no problem.

Good luck, and let us know if you go this route. I'm curious to see if it exposes itself as a serial port. I would also like to see if it would work with a serial OBDII scanner and that maemo-based OBD software.

Incidentally, I have one of those USB to dual-PS2 adapters, and although I didn't hook a mouse up, hooking up a PS2 keyboard worked perfectly.

Re: Trying to come up with a serial port...
 

If a serial converter uses the Prolific PL2303 chip, I'd put money on it working with the 2.6 kernel used by the 770.

I'm also working on getting a Bluetooth > Serial module working...I work for a company that sells them. More for experimenters though, it's a pin header device with 3.3V logic and costs about $60. Anyway I've gotten it to show up in "hcitool scan" and played with some pairing and rfcomm binding, but not quite there yet.

A cable that started in a mini-USB plug and ended with a 9-pin RS232 port would be useful, especially if it had a molded in compartment to hold some AAAs. Wonder how long a couple of lithium coin cells would power a converter like that....many RS232 converters have an openable shell and possibly enough extra space for some coin cells. Actually the one sitting on my desk does...and it has a USB B plug. Now all I need is a mini-USB to B cable.

Re: Trying to come up with a serial port...
 

For that matter, you are dealing with a serial port, so don't you have 5v right there??
http://pinouts.ru/SerialPorts/Serial9_pinout.shtml
Batteries not necessary!

Re: Trying to come up with a serial port...
 

In case I might have stumbled upon something interesting:

http://www.roalan.com/Bluetooth%20Wi...0Converter.htm

I truly have not the foggiest idea whether this fantabulous contraptation would work with an Internet Tablet though.

Re: Trying to come up with a serial port...
 

assuming you can make a usb to serial interface work, how do you send data to it ? does it appear as /dev/tty or what ?

Re: Trying to come up with a serial port...
 

The USB bluetooth adapters are much cheaper and have serial ports (COM) built in.

Re: Trying to come up with a serial port...
 

Looking here shows USB to Serial adapters starting around $7 shipped.
Again, look at my earlier post in this thread where I suggest that you can borrow the 5v from the serial device to which you are connecting. In fact,you might get lucky and find that the 5v pin on the DB9 is already hooked into the 5v suppy to the USB.

Re: Trying to come up with a serial port...
 

I kinda figure that these USB to serial devices have a chip in them that identifies them as a USB serial device, now if the device identies itself as a mass storage device, then the kernel will know what to do with it, will it know what to do with a USB/serial converter

Re: Trying to come up with a serial port...
 

Thanks, Fanoush! Thank you everyone. I'd left my PC hardware reference manuals in my car a few weeks ago, and it was stolen that night. The links to the various pinouts are really appreciated.

Re: Trying to come up with a serial port...
 

I looked at http://maemo.org/community/wiki/howt...f69e45ed6335fc

Did someone find out if this appeared as a device similar to /dev/ttyS1 or not?

Re: Trying to come up with a serial port...
 

I've connected com lines to some kind of connector mounted on my n770 for additional usart but when I enable it via R&D flags I've got reboots from "hands" again and again. Removing these bit's allow for normal boot.
I can't figure why it's keeps rebooting.

Re: Trying to come up with a serial port...
 

I worked on this a while back and got good results.


look at this thread for details ->
http://www.internettablettalk.com/fo...ad.php?t=23033

To test the interface i would suggest linking rx and tx together, opening the port ( i like pyserial for quick dev ) which will appear as a ttyS0 and send data out and it should echo back if you have everything set up correctly.

Re: Trying to come up with a serial port...
 

I wonder if a USB to ethernet RJ45 would be more useful. I see them for ~$5. Anyone yet networked a N770 with one of these?

billj

Re: Trying to come up with a serial port...
 

No, the reason I want the serial connection is because it is more useful. Why is a serial port more useful than a Ethernet connection to a sys.adm who is stuck with a nearly unbootable blade at 1am in a data centre?

There is a chap in Canada who sells known to work RJ45/USB connections for the n770. Cannot remember his web site. Perhaps someone knows?