On Thu, 10 Feb 2011 19:54:13 +1000, SteveG <[email protected]> wrote:
>> >> But when I involve a USB connected serial port (which I have to do if >> I undock my laptop) I get all kinds of strange errors, basically no >> communications at all! I have two different ones but both are >> problematic (ATEN RS232USB and SUNIX 4-port ComHub). >> >> Do you know of any problems related to SynaSer via USB connected RS232 >> adapters on Windows7 or WindowsXP? >> >> Right now I am moving the Lazarus application around to different >> computers (real and virtual) and different COM ports (real or USB >> connected) to try to figure out why it is so hard making it always >> work. And this is when I found that I tried ports that were already >> reserved for the virtual machine or actually unplugged without >> SdpoSerial saying anything about it.... >> > >Dont know if its any help at all, but I am also having serial port >problems using USB adaptors. > >I am developing under Ubuntu using synaser and have found that I can >only connect to the port about once every 5 or so trys. > >Cant say if it is directly related SynaSer/ USB adaptor though, as I >dont have an onboard one to test against. > >side notes - >if I use 'serial port terminal' it connects every time. >if I use 'cat /dev/ttyUSB0 > /tmp/test.txt' it tends to not connect more >than it connects (similar to synaser) > >Suggests it may be necessary to 'reset' the port somehow before using >I have a small sample program for testing if anybody wants it > It is very strange how Windows handles the com ports... Somehow there seems to be some hidden deeper issues that makes some components not work in some situations. Examples: We used a 3rd party serial component in Delphi for many years without real problems (WinNT4, Win95, Win2000 and now XP). But then we encountered a case where the component simply would not trigger any reception events. This happened on a Panasonic wireless gadget that was an extension of a WinXP PC with a touch screen and a few extras like a serial port. We used the serial port for an RFID reader and it simply would not read. If I added a timer and let it poll the component for data then I could make it work for this simple case, but that was a real kludge.. So then I modified the program to use AsyncPro instead and it started working. Don't know why the difference. Later, around 2008, I had another problem with an automation program communicating with a machine tool via RS232. At that time I *was* using AsyncPro, and it worked just fine on my laptop when connected to the machine. But the same software running on the customer's PC:s refused to communicate. These PC:s had *real* com ports and were running XP. So as a test I switched this program over to using the old serial component we used before, and amazingly then it worked just fine! Now I have problems with USB attached serial ports and lazarus programs using SdpoSerial as described in this thread. In this case the comm works fine as long as I use the *real* com port in my docking station. But won't work if I use one of the 4 com ports in my newly bought SUNIX ComHub UTS2009P4 or for that matter if I use a USB single channel com port adapter from ATEN. But the latter can be used if it is not transferred to the virtual machine where I develop the software. Really very confusing, and I was not planning on doing research into this. I was programming a comm application for data collection.... Do you think there is any chance of using my old serial component (housed in a single pas file) with lazarus? It is a Delphi component and I don't know what you need to do in order to use it with lazarus. I realize that it would not work as a cross-platform unit but could be interesting for testing. In the end of course what I need to do is to get it working on the embedded ARM system with Linux. -- Bo Berglund Developer in Sweden -- _______________________________________________ Lazarus mailing list [email protected] http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
