My favourite RS-232 stories.
I had to make a cable to a HP Paintjet that some nong had purchased with a serial port instead of a parallel port. It needed all the signals because it couldn't buffer much data and had to tell the PC when to stop sending. After months of attempts with a simple cable, and quantities of wasted paper, I found the manual and followed the instructions. Worked perfectly after that.
And then there were the cases where you two serial terminal devices needed to see each others' control signals. The idiot comms guys kept giving me cables where the control lines were just reflected back at each end. This did not make for reliable communication! Again, I made a proper null modem cable over the objections of the comms guys and things were a lot more reliable after that!
Wade.