jeffrey@ccnysci.UUCP (Jeffrey L Bromberger) (01/12/89)
After booting the diagnostic disk for my UNIX-PC, when I wanted to test
the serial port (/dev/tty000), it said I needed a special plug. How
should one wire this? Is there a source for getting one ready-made?
The reason I ask is that I believe that my serial port is dead. Any
help would be greatly appreciated. Thanks.
--
Jeffrey L. Bromberger
System Operator---City College of New York---Science Computing Facility
Anywhere!{cmcl2,philabs,phri}!ccnysci!jeffrey jeffrey@ccnysci.BITNETdca@kesmai.COM (David C. Albrecht) (01/14/89)
In article <1154@ccnysci.UUCP>, jeffrey@ccnysci.UUCP (Jeffrey L Bromberger) writes: > After booting the diagnostic disk for my UNIX-PC, when I wanted to test > the serial port (/dev/tty000), it said I needed a special plug. How > should one wire this? Is there a source for getting one ready-made? > The reason I ask is that I believe that my serial port is dead. Any > help would be greatly appreciated. Thanks. > -- Okey dokey. Many moons ago I had a strangeo problem with my tty000 unixpc port where it would ask for user but never the password. It turned out some of the signal lines were fried. Fortunately the fried ICs were line driver chips easily obtained at the local Radio Shack. Unfortunately, they were soldered to the board and thus I had to pull the motherboard to fix them. I figured (correctly I believe, its been a while) that the serial port test was essentially a loop-back test where it runs the output lines for the port into the input lines for the port and handshakes with itself. I got an appropriate cable using a ribbon cable which I had that has both male and female connectors on each end. I simply put a null-modem adapter in between the male and female connectors on the far end of the cable and then plugged the other end into the serial port and voila!, a test cable. David Albrecht