so, one week ago I got a phone call by a customer claiming that some of his equipment was not working and they sent me the whole inside a parcel. They assembled the cables by their self, and the software doesn't use any handshake, but rather a NULL-modem setup, which weirdly manifested a randomly bad behavior, so they phoned me thinking the problem was in the electronics.
After some inspection, I found out that pin 7 and pin 8 on their RS232 serial cable are swapped.
Pin7 is RTS, input
Pin8 is CTS, output
This means that the host (a laptop? a computer? whatever they used) had its CTS signal wired to the CTS signal of the equipment, two outputs signals wired together in a collision.
host CTS --------------?-------------- CTS equipment
I haven't visited this customer yet, and I wonder if this kind of mistake in cables wiring can cause permanent damage.
What do you think?