On Thu, Oct 18, 2012 at 9:14 AM, Juan Pablo Carbajal <ajuanpi+...@gmail.com> wrote: > On Thu, Oct 18, 2012 at 12:31 AM, Juan Pablo Carbajal > <ajuanpi+...@gmail.com> wrote: >> Hello, >> >> I am observing weird behaviors and I couldn't pin down at which level >> things are going bad. Using instrument-control 0.1.0 from Forge. >> Running Ubuntu 12.04 64 bit >> Linux 3.2.0-32-generic #51-Ubuntu SMP Wed Sep 26 21:33:09 UTC 2012 >> x86_64 x86_64 x86_64 GNU/Linux >> >> I am using serial communications. I am testing with a physical >> loopback (RxD connected to TxD) in this USB2Serial adapter >> https://www.sparkfun.com/products/718. >> >> Problem 1 [Ring bufffer?]: >> s = serial (); # 8-N-1 >> srl_baudrate (s,9600); >> >> srl_write(s,"hello") >> ans = 5 >> >> char(srl_read (s,5)) >> ans = hello >> >> char(srl_read (s,5)) >> ans = hello >> >> char(srl_read (s,15)) >> ans = hellohellohello >> >> char(srl_read (s,4)) >> ans = hell >> >> char(srl_read (s,6)) >> ans = ohello >> >> It looks like as if the buffer is a ring buffer or is really big and >> filled with "hello". Maybe flushing the input after reading will solve >> the problem? Continued from the example before I got this >> >> Problem 2 [Hang after flush]: >> srl_flush (s, 1) >> >> char(srl_read (s,5)) # This blocks as expected but ... >> srl_read: Interrupting... >> ans = >> >> srl_write(s,"hello") >> ans = 5 >> >> char(srl_read (s,5)) # This also blocks!!!! >> srl_read: Interrupting... >> ans = >> >> The only way of getting things to work from this point on is to close >> the port and open it again. >> >> Can anybody reproduce this? any suggestions of tests to run to see >> whether the problem is at hardware level? >> >> I also tested with a virtual loopback (command "socat -d -d PTY: >> PTY:", this is simpler than the suggestion in the wiki. I can update >> that), I do not observe Problem 1, but I can't interrupt the second >> call to srl_read >> >> s = serial("/dev/ptmx", 9600); >> srl_write(s,"hello") >> ans = 5 >> char(srl_read (s,5)) >> ans = hello >> octave:5> char(srl_read (s,5)) >> srl_read: Interrupting... >> srl_read: Interrupting... >> srl_read: Interrupting... >> srl_read: Interrupting... >> >> >> Thanks > > Testing in Debian Squeeze 2.6.32-5-686 with the same hardware > configuration doesn't show Problem 1 > Note that: > > - Ubuntu 12.04 uses kernel 3.2.0 and the driver controlling the adapter is > ftdi_sio: v1.6.0:USB FTDI Serial Converters Driver > > - Debian Squeeze uses kernel 2.6.32 and > ftdi_sio: v1.5.0:USB FTDI Serial Converters Driver > > > In Debian the problem observed is the following (opening the port the > same as before) >> srl_write(s,uint8(127)); srl_read(s,1) > ans = 127 >> srl_write(s,uint8(128)); srl_read(s,1) > ans = 0 > > Should it go up to 255?
Additional update. Checking the code of srl_write.cc and srl_read.cc I noticed that while srl_write writes "unsigned char" srl_read reads "char". Is this intentional? Additionally there is a C style cast in srl_write line 63. I assume it should be a static cast and therefore it should be buf[i] = static_cast<unsigned char>(data(i)); Or is there a reason why to do it the C way? ------------------------------------------------------------------------------ Everyone hates slow websites. So do we. Make your web apps faster with AppDynamics Download AppDynamics Lite for free today: http://p.sf.net/sfu/appdyn_sfd2d_oct _______________________________________________ Octave-dev mailing list Octave-dev@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/octave-dev
