Hi guys! I just got my Arduino a little while back and have a quick question.
I have a GPS that has a serial output. I removed the atmega8 from the board, and connected the Tx and Rx pins on the Arduino board to the corresponding ones on the GPS. I set the GPS to ASCII output at 9600 baud and plugged the Arduino board into my usb port on my computer. When I went to the serial monitor, the data from the GPS came in fine. I changed the setting on my GPS to the standart communication and opened an app that takes data from a GPS. I set the port to the serial usb driver I installed for use with the Arduino, but it did not commuinicate with the GPS at all. Does anyone know why?
After reading this, I realize this isn't a very quick question. 
What do you mean by "I changed the setting on my GPS to the standart communication and opened an app that takes data from a GPS"? What setting was the GPS in when you tested it with the serial monitor? Did you try using it with the serial monitor after changing the setting?
the NMEA standard serial communication speed is 4800 baud. Your other application may be expecting 4800 instead of 9600.
-j
What do you mean by "I changed the setting on my GPS to the standart communication and opened an app that takes data from a GPS"? What setting was the GPS in when you tested it with the serial monitor? Did you try using it with the serial monitor after changing the setting?
I guess that wasn't very clear. The GPS has many different serial communication settings. One of them is the standard for communication with GPS applications on the computer. When I tested it with the serial monitor, I had it set to ASCII output at 9600 baud. The serial monitor got the messages from the GPS fine, but the GPS application on the computer did not recognize the GPS set to the standard communication setting. I realize now that this isn't really very Arduino related, but I just wondered if you guys had any idea what was wrong.
the NMEA standard serial communication speed is 4800 baud. Your other application may be expecting 4800 instead of 9600.
-j
Yes, but I am not using NMEA. I was using the "Garmin" communication setting. I will try that, though, to see if NMEA works with the GPS app on my computer.
Possibly a bit fundamental here - the output of your GPS is probably at RS232 levels - i.e. +/- 12V, the serial lines on the input of the USB chip are at 0 and 5V levels. Doing this might blow up the USB chip on your NG board, I would not recommend it!