Swap the tx and rx lines on the Arduino. Swap back to reconnect to PC.
> On Jun 3, 2015, at 10:51, Chris Albertson <[email protected]> wrote: > > In the RS-232 world devices are either DTE or DCE. You need one of > each on each end of the line if using a normal straight cable. To > connect two like devices you need a crossover cable (AKA "null modem") > From the sounds of it I'm guessing the PC is a DCE and the Arduino > and Thunderbolt are both DTE. > >> On Tue, Jun 2, 2015 at 9:38 PM, Dan Quigley <[email protected]> wrote: >> Hello, >> >> I'm integrating an Arduino (Due/Mega have tried both) with a surplus >> Thunderbolt and need some advice. >> >> The Thunderbolt is a known working unit (supplies 10Mhz to my HPSDR rig) and >> the serial interface works fine between it and a PC. I've read the coverage >> about this kind of integration (and some of the archived discussions on this >> board) and am employing a commercially available MAX232-based "shield" >> (RS232 V2) to handle the level translations. Just three lines (RX/TX/GND) >> are used. The MAX232 circuit is working, reliably passing data between the >> Arduino and a PC. >> >> With the Thunderbolt is connected to the MAX232 no data passes. Activity >> LEDs on the non-RS232 of the MAX232 circuit show no activity when the >> Thunderbolt is providing data, indicating the MAX232 is not performing the >> intended level translation. I've scoped the RX/TX lines coming from the >> Thunderbolt both when connected to the Arduino and not. There is a distinct >> difference. When disconnected, the pulses are about 10.3v and nice, crisp >> and square. Connected, the pulses are ~50% lower in voltage (4.1v) showing >> an exponential rise in voltage and trace noise. >> >> I'm pretty much stumped at the moment and wonder if anyone can offer a >> suggestion or thoughts on a direction to take. >> >> Thanks in advance, >> Dan Quigley (N7HQ) >> >> >> _______________________________________________ >> time-nuts mailing list -- [email protected] >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. > > > > -- > > Chris Albertson > Redondo Beach, California > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
