karron@MCIRPS2.MED.NYU.EDU (09/09/90)
After checking all of the subtle possibilities, I was refered to check the obvious: cables. I tested my cables, and they seemed ok. I then tested the ports with a paperclip (to loop back TD-RD, CTR-RTS, and DCD-DTR ) and eliminate problems with cables. The problem persisted, and pointed to inside the machine. I opened the back, and using a can of contact cleaner, blew out lots of dust, dirt, and junk. Cleaned the boards and the ribbon cable card edge connectors, and reassembled. the problem was gone. My machine is well over three years old, gets moved a lot, and has worked very dependable so that it is not opened up much. Sorry for the fuss, and I am very happy with hardware handshaking at high serial io speeds, > 9600 baud. I have been running test overnight, and there have been no lost characters. My thanks to Vernon Schryver, (who implimented RTS-CTS on the 4D machines) for patiently holding forth that my problem was cables, even when I did not think that it was the cause of the problem. dan. +-----------------------------------------------------------------------------+ | karron@nyu.edu Dan Karron | | . . . . . . . . . . . . . . New York University Medical Center | | 560 First Avenue \ \ Pager <1> (212) 397 9330 | | New York, New York 10016 \**\ <2> 10896 <3> <your-number-here> | | (212) 340 5210 \**\__________________________________________ | +-----------------------------------------------------------------------------+