The first thing to check when receiving junk over a serial port: is the baud rate correct? (Also databits, parity and stop bits, although that's almost always 8N1 nowadays.)

How do i know what is being read in $saw1/$saw2 is correct ?

What do you expect to receive?

If you want to see what's going over the wire, do you have some other way to monitor the serial port, like using a software or hardware device (even an oscilloscope)?

In reply to Re: Using Device::SerialPort by Anonymous Monk
in thread Using Device::SerialPort by hardy004

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