Messages in this thread | | | Date | Tue, 04 Apr 2006 14:32:36 +0100 | From | Ian Leonard <> | Subject | Serial port problem |
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Hi,
The trouble started when I upgraded a machine from FC3 to FC4. It had a serial touchscreen. With FC4 it stopped working completely. I added debug to the X input driver and found read() permanently blocked despite the file having been opened with O_NDELAY.
I then tried a simple test with two machine connected with a serial cable and using minicom to send characters both ways. One was a laptop. If you typed from the failing machine to the laptop all was well. Typing the other way caused one character to be displayed and then it hung (although I could use 'cat >/dev/ttyS0' to send data just fine).
I then repeated the test using 4 different motherboards. 2 exhibited the problem 2 didn't. So to recap, sending data without changing the driver settings (stty) seems to work. Configuring the port seems to cause a problem on some motherboards. One of those is a VIA mini-itx. The other is more standard Gigabyte.
I have tried using the standard FC4 kernel and 2.6.15.6.
Not sure what to try next, so any pointer gratefully received.
-- Ian Leonard
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