Serial Interface doesn´t work correctly

[motog]

Hi,

I installed VB 6.0.4 (Host W10 17763.379) and I use an old equiqment to transfer data to a virtual XP using the serial interface. I am using Port 1, COM1, Host-Interface, Pipe/Socket aktivated, Adresse COM1. The transfer starts but after a fewsecond it terminats. If I downgrad to VB 5.2.26 it work correctly.

Sorry about my bad enlish.

Best regards Jürgen

[Socratis]

1. It's usually better and faster, if issues get first addressed in the ​VirtualBox forums, a lot more eyes there. More than 95% of the issues are resolved in the forums, which keeps the developers focusing on the bug fixes and enhancements, and there is no need for another ticket to keep track of. For example, yours is most probably not a bug and someone from the developers has to deal with it and close it as "Invalid".

Plus a discussion and analysis on the bug tracker is going to help you, me, and potentially a future drive-by user or two. Not so in the forums, many more tend to benefit...

So, if you can, please open a new thread in the ​VirtualBox on Windows Hosts section of the forums. Please be sure to mention that you came from the bug tracker and include the ticket number.

2. You were supposed to follow these steps when you filed the bug, and provide a VBox.log:

   Attach a (full) log file ("Machine" menu/"Show Log" in the main VirtualBox Manager window) straight away to save time for you and for us. The log file contains a lot of useful information about both the host and the guest systems as well as information about what happened during a particular machine run. Please do not cut and paste it.

[hykwok]

Try to use the latest 6.0.x test builds. If your problem is solved, then it should be related to this bug #18319.
However, the communication might be broken again after your application is restarted. You can restart the virtual machine again to solve the problem for the latest test builds.

[hykwok]

I have tested the VB 6.0.6 and my application, that uses serial port, cannot not work correctly after restart.
After the virtual machine (VM) start, my application works.
If I close the application and restart it again, it does not work
If I reboot the guest OS, my application does not work
If I shutdown the VM and restart it, my application works again.

Actually, in the bug report #18319, I found that VB 6.0.6 will not send the latest received byte to the guest OS. In the VB 5.2.26, I do not encounter this problem.

[aeichner]

As I wasn't able to reproduce the issue so far we need some special logs from the serial port emulation. I prepared a testbuild which can be downloaded from here, look for the latest development testbuild (6.1.2+ state). In order to activate the tracing the VM needs some special config which can be added with

VBoxManage setextradata <VM name> "VBoxInternal/PDM/DriverTransformations/SerialTrace/AboveDriver"                         "Host Serial"
VBoxManage setextradata <VM name> "VBoxInternal/PDM/DriverTransformations/SerialTrace/AttachedDriver/Config/TraceFilePath" "<trace/log/file/path>"
VBoxManage setextradata <VM name> "VBoxInternal/PDM/DriverTransformations/SerialTrace/AttachedDriver/Driver"               "IfTrace"

<trace/log/file/path> needs to be substituted with a file path the user as write access to. <VM name> needs to be substituted with the VM name being traced. The current setup doesn't work if you have multiple serial ports configured which are using a host serial port device, so be sure to either disable all but one or leave them disconnected. Depending on the size the resulting logs can either be attached to this defect (they don't contain any data being transfered but only metadata about timings and parameters of certain function calls) or can be sent directly to Alexander (dot) Eichner (at) oracle (dot) com.