Thanks for the update - it's strange, and unfortunately I'm running out of ideas at the moment... I use the IO::Termios+IO::Stty combination on a Raspberry Pi myself, running a stock Raspbian, to read multiple FTDI chips and other dataloggers at once, and it works fine. Did you compare the strace results of the shell and the Perl scripts to make sure the same thing gets sent? Are you certain there are no other processes on the system trying to open/read the port? For example, did you make sure to kill all the cat processes you backgrounded, and check for other daemons? For example, I once had trouble with gpsd trying to get to the serial port when I was trying to use it as well, or that website mentions a vzlogger process that is included as part of the image.

In reply to Re^5: r/w attached infrared head on /dev/ttyUSB0 by haukex
in thread r/w attached infrared head on /dev/ttyUSB0 by stoerti

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