serial ports and 2.2.1

serial ports and 2.2.1

Post by Joe Pfeiffe » Tue, 23 Feb 1999 04:00:00



I've got a couple of applications which ran fine with 2.0.36, but
which have not worked properly with 2.2.1.  In both cases, the problem
appears to be in the serial port.  Both communicate with other
devices.  Both used /dev/cua? devices under 2.0.36, and neither (without
modifications) have worked with either cua? or ttyS? ports under 2.2.1.

The first, which I wrote, is a program downloader for Motorola HC11
boards.  I was able to get this one to work (using /dev/ttyS?) by
inserting a tcflush(fd) call after every write (in general, due to the
protocol used by the HC11 bootstrap, there is a read following every
write).

The second, which was written by somebody else, is a data transfer
program for PalmPilots.  He's been mystified by my bug reports; the
tcflush() trick didn't work for this program.

So -- does anybody have any ideas as to what may have changed in the
serial driver that might be related to this?
--
Joseph J. Pfeiffer, Jr., Ph.D.       Phone -- (505) 646-1605
Department of Computer Science       FAX   -- (505) 646-1002
New Mexico State University          http://www.cs.nmsu.edu/~pfeiffer

 
 
 

serial ports and 2.2.1

Post by Joe Pfeiffe » Tue, 23 Feb 1999 04:00:00


Brain fade....  somehow, in describing this problem, I managed to
fat-finger tcdrain all the way to tcflush.  What I meant to write was:

I've got a couple of applications which ran fine with 2.0.36, but
which have not worked properly with 2.2.1.  In both cases, the problem
appears to be in the serial port.  Both communicate with other
devices.  Both used /dev/cua? devices under 2.0.36, and neither (without
modifications) have worked with either cua? or ttyS? ports under 2.2.1.

The first, which I wrote, is a program downloader for Motorola HC11
boards.  I was able to get this one to work (using /dev/ttyS?) by
inserting a tcdrain(fd) call after every write (in general, due to the
protocol used by the HC11 bootstrap, there is a read following every
write).

The second, which was written by somebody else, is a data transfer
program for PalmPilots.  He's been mystified by my bug reports; the
tcdrain() trick didn't work for this program.

So -- does anybody have any ideas as to what may have changed in the
--
Joseph J. Pfeiffer, Jr., Ph.D.       Phone -- (505) 646-1605
Department of Computer Science       FAX   -- (505) 646-1002
New Mexico State University          http://www.cs.nmsu.edu/~pfeiffer