Gene,
I tried a pl2303 serial to USB one and had problems. It was a radio
shack branded device.
Using FC4 at the time it looked like only every other character was
being received by the host. Data to the device was fine. Unfortunately,
I never resolved the problem and opted for a four port Keyspan device.
No problems connecting through it to the same serial device.
If the Garmin only has four wires, most likely the handshake is
XON/XOFF, if any. Does the Garmin "talk" correctly via one of the "real"
serial ports?
Bob...
Gene Heskett wrote:
Greetings;
Trying to get roadnav to talk to my elderly Garmin 12, and because I'm out
of serial ports, the garmin 4 pin to db9 connector cable is plugged into
the db9 end of a pl2303 serial to usb adaptor. The pl2303 is recognized
and assigned to /dev/ttyUSB0 according to dmesg.
I'm apparently getting zero data from the garmin and I suspect its the
lack at least the 7 wire protocol at the garmin side of the pl2303. I
believe it may even be just a 2 wire & ground setup as the garmin
connector is only a round 4 pin, probably with little or no flow control
as the garmin apparently runs at 4800 baud only.
But, I'd like to ask here on this list: Has anyone ever made a pl2303
based adaptor actually work?
The only other time I seriously tried to use this $40 gizmo was as an
interface translator with the rs-232 pack of a vintage coco on the other
end. At that time I was able to type back and forth using terminal
programs on both, but a known good zmodem setup on the coco failed to
move more than about 10 bytes of a 10k file when I had minicom attempt
the transfer. At the time I also suspected config/handshake problems and
eventually gave up, but now I think the pl2303 may be busted or
miss-configured, hence the request for a gui program to monitor
individual wire status at the db9 connector, but do it
using /dev/ttyUSB(x).
Is this latter idea even possible?
Thanks everybody.
