they are the same for perl, but they are not the same for the device on the serial port.
the device treats them differently.
the issue is not really perl, but what ways there are to send the same data in different ways, which might get interpreted differently.
a more confusing example:
print "\x36" is 6 in perl, is 54 on device if decimal is expected
print "6" is 6 in perl, is 6 on device
the issue is primary how the device handels the data, which is different on most functions as well.
kind regards - alex