Grigorios Prasinos wrote: > I am trying to connect my Garmin etrex legend gps (old model) with my Zaurus > C750 that runs Angstrom 2007.12. > I have an original Sharp serial cable and the etrex cable. Both are 9-pin > female so I use a gender changer in between (I do not know if the gender > changer crosses wires, but I do not think so).
Well, the original Sharp CE-170TS serial cable is poorly designed and makes non-trivial assumptions on the serial port it connects to. There is no voltage convertor, and for some pins even no protection (wiring CPU GPIO pin directly to the cable): http://www.penguin.cz/~utx/zaurus/photos#ce-170ts If the opposite serial cable has the same poor design, then it will not work - each one expects to get +-12V juice from the opposite. In my test it worked with computer serial port and analog modem, but did not work with mobile phone cable, GPS and cheap usb-to-serial convertors. There are three chances: - If you have anything older than SL-Cxx00, you can try third party Z-Thincable serial. They may work better with SL-Cxxx and SL-5500, but they don't work with SL-Cxx00. - If the opposite device uses 3.3V-TTL serial levels, you can create a custom cable without voltage convertors. You will still need invertors for TxD and RxD lines, because Sharp inverts its levels for historical reasons (or you can try to knock-out the invertor inside Zaurus). - Design a real fully RS-232 conforming serial cable. It needs just connectors, two 3.3V-TTL invertors and a 3.3V powered 3.3V-TTL<->RS-232 chip. Designing a fully featured serial cable working with SL-Cxx00 is in my TODO list, but don't expect any output soon. I can provide all information I have (plus my order) to anybody, who wants to design it. ________________________________________________________________________ Stanislav Brabec http://www.penguin.cz/~utx _______________________________________________ Angstrom-distro-users mailing list [email protected] http://lists.linuxtogo.org/cgi-bin/mailman/listinfo/angstrom-distro-users
