- Sun May 27, 2012 10:55 pm
#145095
I've had my Venus 638FLPX for several months on my AVC robot with no problems. It was working yesterday just fine. Tonight I went to use it and discovered problems with serial comm. I get gibberish for any baud rates from 1200 thru 230400. This is on the PC using SFE 3.3V FTDI breakout. The robot isn't able to read NMEA off of it either which is what prompted me to check on the PC.
The GPS is configured for 10Hz output rate and NMEA messages. It was working great for hours last night. I did leave it plugged in and running all night last night but I've done that a dozen times before with no problems.
I put the GPS TX line on the scope and the edges look square, and there are pulses coming through and no noise that I could see. The scope I used is very basic so couldn't isolate a waveform to estimate baud rate. I guess I'll have to dig out the good scope.
Is there any way to reset it if I can't communicate with it? For now I've pulled the backup battery and am crossing my fingers that tomorrow morning it'll behave sanely again.
Naturally this has to happen with only a few weeks before the AVC when I'm already desperately battling a new bug that's jacked up the robot's nav accuracy. Gotta love it.
Any ideas of what's wrong or what I could try?
The GPS is configured for 10Hz output rate and NMEA messages. It was working great for hours last night. I did leave it plugged in and running all night last night but I've done that a dozen times before with no problems.
I put the GPS TX line on the scope and the edges look square, and there are pulses coming through and no noise that I could see. The scope I used is very basic so couldn't isolate a waveform to estimate baud rate. I guess I'll have to dig out the good scope.
Is there any way to reset it if I can't communicate with it? For now I've pulled the backup battery and am crossing my fingers that tomorrow morning it'll behave sanely again.
Naturally this has to happen with only a few weeks before the AVC when I'm already desperately battling a new bug that's jacked up the robot's nav accuracy. Gotta love it.
Any ideas of what's wrong or what I could try?