On Friday 14 August 2009 16:19:04 Grant Edwards wrote: > On 2009-08-14, Hendrik van Rooyen <hend...@microcorp.co.za> wrote: > > In the meantime I have had another idea which I have also not tried yet, > > namely to do independent opens for reading and writing, to give me two > > file instances instead of one, and to try with that. I have no idea if > > it would make any difference, or even work at all. > > That should work (and shouldn't make any difference) > > > My normal stuff works, but I do not like it as it is > > essentially busy looping with short sleeps in between. In the > > eBox, it uses most of the processor just to move a few bytes > > of I/O in and out between the serial port and the TCP/IP, and > > struggles to do that better than five times a second, while > > the message time on the 115200 baud port is only about 2 > > milliseconds. > > What platform are you using? I suppose it's possible that > there's something broken in the serial driver for that > particular hardware.
Your experience seems to be exactly the opposite to mine - you are saying it should "just work" and I am seeing half duplex functionality. I have seen this on my development machine which is a dual processor of some gigs running SuSe Linux 10.3, as well as on the other end of a the scale - the eBox (a 400MHz 486 without floating point with 128 Mb of memory) running Slackware. Maybe it is in the way I set the port up, because that is the common thing. What I do is this: reterror = os.system('stty -F /dev/ttyS0 sane 115200 cread clocal raw -echo') It does not seem to make a difference if I do this before or after opening the port. Any comments from a Linux Guru? - Hendrik -- http://mail.python.org/mailman/listinfo/python-list