Delphi 7 XP prof UC310 USB/RS232 converter
I dont think that this problem is related to Delphi as such, but the basic problem is that if I open a port whilst a continuous flow of data is being supplied to it (in this case, a weighing machine at 9600,n,7,1 - a repeated simple sequence of ' 1.234 Kg CR+LF') sometimes the whole machine will reboot (I have tried two different machines, two different USB converters and two different Delphi components in my software ('comport and asyncpro').
There is a reboot due to data entering the PC via the USB converter if the port is opened or closed whilst data is being input. This is an intermittent problem and it must be due to some kind of internal buffer overflow.
Note that this problem does not occur if the port is a standard PC serial port.